As a Swiss citizen, who once was pro-European-Union, I have the following things to say:
- on which country
- on whether or not the country in question is a member of the Schengen-area
- on which stakeholder within the country
- and on what the geopolitical/military consequences of such an exit would be
Let's first clarify a few fundamental things.
First, there was the European Union (EU)
Then, for those
candidate countries that would kind-of have a limited membership/reservations (Iceland, Liechtenstein, Norway, Switzerland), the
European Economic Area (EEA) was created
This European Economic Area is a Free-Trade area between the European Union and the European Free-Trade-Area (EFTA)
And a few points about Switzerland first, since it came up in other answers:
Naturally, the political establishment in Switzerland wanted to join the EEA, because it wanted access to the EFTA. However, Switzerland is a direct democracy, and joining a Free-Trade-Area requires a change in the code of law, which requires the new law to get a majority vote (in a referendum).
So the government/political-establishment cannot just decide that, like it could in pretty any other country; they need to get a majority vote. But in reality not the entire political establishment was for joining (evil tongues claim this is because the EEA contained minimum-wage-rules, which at the time, and to this date, do not formally exist in Switzerland ). So on the base that a EEA-membership would allow Germany/French/Italians to work in Switzerland in "unlimited quantities" (remember, the Berlin wall fell 3 years earlier, and saw a migration of a big lot of poor East-Germans (GDR-citizens) westward), fear about unemployment and salary-dumping was generated, and successful because Switzerland was in a pretty bad recession at the time. As a consequence, the voting (not an election, but a vote about the law-to-be) was hold on the 6th of December 1992, and it saw a 50.3 % NO-majority (by the way, it also failed in the Swiss equivalent of a upper-chamber/senate, with 16 out of 23 being no-votes).
Naturally, the outcome of the vote was not in the interest of the government, so in 1995, they tried a backdoor-entry via the initiative "for an immediate membership in the EU". It demanded immediate start for membership-negotiations (and thereby EFTA-membership). This initiative was voted-on on the 4th of March 2001, and it saw a 76.8% NO vote.
However, long before that 2001-vote, the government had to concede that they could not get a vote about EFTA membership through the voting process as long as freedom of movement and residence (and thereby work) was contained in it (aka Schengen-agreement).
But the prospect of being a EU-external-frontier (trade tariffs, delays, trade obstructions/barriers) was not very desirable for the industry in Switzerland. So the government started negotiating bilateral agreements between the EU (includes negotiations with all the EU's member-states) and Switzerland.
However, negotiations were very difficult, and the EU-east-enlargement stood in front of the door. Because after the enlargement, Switzerland would have had to negotiate with that many more countries, they tried to finish the negotiations before the enlargement. It was claimed that they tried their very best to prevent having to sign the Schengen agreement, but that it simply could not be done, and that it's better to take the winnings of those negotiations instead of renegotiate with about 10 more countries. Then there was a referendum at the 21st of Mai 2000, in which the referendum against these contracts was taken, and lost, So the contracts became effective as of June 1st 2002. In 2005, Schengen was accepted (the sheep majority of 55% was afraid of what would happen to the industry, and therefore their jobs, if they didn't). So, de facto, these bilateral-contracts are quite the same as EEA-membership, with perhaps a few better terms (like no minimum wage, or automatic adoption of EU law, instead it is semi-automatic). The Schengen-agreement came into effect on the 12th December 2008.
Then in 2009, the sheep voted to extend the free movement of people (=freedom to work in Switzerland) to Bulgaria and Romania by a 59.6% majority in favor, because their government promised "flanking arrangements" in case too many people come and create an unemployment or dumping problem. In practice, these promises turned out to be nothing more than hot air.
Since then, the economic situation has become progressively worse, particularly because of salary dumping and rising unemployment. Correspondingly, social security has been reduced/cut, while corporate taxes were lowered. In February 2014, a initiative was brought to a vote, which demanded to create law limiting the freedom of movement of foreign citizens to Switzerland. It passed, but the consequences would entail the renunciation of the Schengen-agreement, and, absent agreement otherwise, the triggering of the Guillotine clause collapsing the other six bilateral agreements (=cutting EFTA membership).
A) It depends on which country. In terms of contributions, Germany and the UK would be much better of if they left. Most Eastern-European and Southern-European countries on the other hand, would be in a world of trouble.
Would a country that left the EU lose anything more than just funding
they receive from the EU?
Yes, they would loose access to the EU R&D funds, and for example, the student-exchange program. They would also loose access to ECB money. Forthermore, you could loose freedom of movement and residence (you couldn't work in Germany or Switzerland or Austria or Luxemburg, for example). Also, you'd loose on the EU agricultural subsidies (last time I heard, they make up 51% of the entire EU's budget, now - talk about madness)
I've been told the UK would be worse off but how exactly would it be?
Because you'd no longer be an EFTA member, you'd be an EU exterior border, subject to tarifs and trade obstructions. If you wanted to export something to all European countries, then first you needed to pass through several othern countries (e.g. via ferry from Dover to Calais, then by lorry through France& Germany to Poland, you'd need to negotiate the passage through France, Germany, before you could begin customs proceedings in Poland. You'd also have to comply with any national legislation, which is different in every EU member country. You'd be a lot slower, plus more expensive plus far less flexible than a German competitor who can just drive through wherever he wants whenever he wants, with however much he wants (OK, granted that's an oversimplification, but you get what I mean).
Could a country that leaves the EU not just copy the EUs policies that
it likes and get rid of the ones it doesn't?
Yes it could. But be careful. Knowing all those sanctimonious politicians, that can mean getting rid of the minimum-wage-regulations. It can also mean overruling the European court of human rights, or the EU criminal court. If UK politicians want to get rid of these two institutions overruling national UK sleaze-justice (requiring royal approval & with an unwritten constitution), this is not necessarily a good thing.
If this is the case would countries not be better off without the EU
because they get more control over their own countries?
Considering the amount Germany pays into the EU, and what it gets out of it (e.g. from Greece "rescue-credit"-à-fonds-perdu, or from Czechia/Slovakia financing flat-tax and tax-exemptions for corporations via EU money for building industry, which is actually used to suck industry from Germany to Czechia/Slovakia, ironically financed by taxes raised in Germany which reduce investment in Germany and also financed by state cost-cuttings in infrastructure + R&D spending as well as reducing pensions), we could establish with probability bordering on certainty that Germany would be better of if it wasn't a member of the EU, especially considering how much the value of the Euro has been lowered by the ECB to support the monetary bottomless-pits known as Portugal, Italy, Greece and Spain (and France). Remember, if money-printing is the source of inflation, the looser is the one who has no debts and lots of assets.
So would the UK, most probably. It is worth pointing out at this point that the German chancellor Helmut Kohl agreed to the Euro because it was a condition imposed by France on German re-unification (read: the short-term benefits of German reunification for
Germany Helmut Kohl & Co.'s personal financial bottom-line and political gain outweight the long-term-disadvantages of the ECU). Also, Germany was against taking Greece into the Euro, but agreed to it because France (or rather France's leaders) wanted it so.
However, if you boot for example Greece out of the EU, that means Russia can get its foot into the Mediterranean (and the Dardanelles), which would strategically be profoundly unwanted. Same thing with certain eastern-European countries. Namely, if China gains a hold in Hungary, its cheap cars can roll via the port in Piraeus into Hungary, and from there into the EFTA, where they can wreak havok big time. Also, the long-term benefits of Poland now being the buffer-zone between Western-Europe and Russia in a potentially hot war probably outweighs most economical considerations.
Furthermore, if you're paymaster, you can dictate terms (or at least you're supposed to).
To quote Publius Quinctilius Varus (an old German proverb)
With Friends Like These, Who Needs Enemies?