The problem was not only the process of law-making itself. The new law would certainly have been written in a few weeks and become effective if everyone had agreed in the first place that it was be the best, but this wasn't the case at all.
The situation was and still is very complex. In Germany it had been a long practise to assume the owner of an Internet access point was liable for anything that happened there.
This may or may not be surprising seen from the legal system where you're from, but you have to admit there are also strong arguments in favor of the former German approach. If kids download copyrighted material from the house Internet, they're not legally liable because of their age, so why should you conclude that parents don't have anything to do with it either? Obviously the education of their kids should be their responsibility, and they shouldn't just be able to shrug their shoulders if their kids do anything illegal.
They may be not liable penally, but at least they may be liable financially.
It's a similar thing to that the driver of a car is fined if anyone in his car isn't buckled up as opposed to just the person not being buckled up. The driver is in charge, he underwent drivers training, he signed the contracts, so he's liable.
Everybody agreed that this was a tough situation with respect to Internet access points because it wasn't even prohibited to have or offer or use one, just if you offered it to anyone, you were liable for anything that anybody did, whether it be your private friends or anonymous customers in your café.
Even though, in the decision making process to actually change the legal situation the difficult point was that nobody could really offer an even nearly equal alternative to copyright owners. It is a fact that there are thousands of copyright infringements on the Internet every day. It's also a fact that the state must prosecute them, it's also a fact that copyright owners have a right for financial compensation. Likewise it's a fact that the idea of copyright was never at the disposal.
Now the problem is if you want to prosecute these infringements in a practical and effective way, you often need the liability of the owner of the Internet access point. If he's not liable, in many cases it's a hundred times more difficult to find the person who did anything illegal and prove it that they did. This is due to technical limitations of the architecture of the internet, legal limitations when it comes to logging private data, a general hesitation in the German mentality to accept investigative tools that tap computers, and a couple of other factors.
Thus the difficult point was to weigh the interests of copyright owners, who occasionally spend hundreds of millions (as in the case of Hollywood movies) to create their works, and who have a right for setting the price of the products of these investments as well as a legal right that that right is enforced by the state.
The legal situation is formally in their favor too, and that is with good reasons, but if practically even the most serious infringements are near impossible to be prosecuted, this is an unbalance in the legal situation that needed long discussion in all involved boards before it could be accepted by a majority.
Think about it, if everybody could make free use of your hard work without paying anything, and profit from any expensive financial and other investments you made in the past, it would be very discouraging for you to do extraordinary things in the present or in the future or make similar investments again. You would not bring in your full potential anymore, and if a legal situation encourages a development where this might happen to many people on an everyday basis, especially as more and more work nowadays has immaterial results that can be copied easily, it's definitely an issue a legislator has to be concerned about.
Free WiFi is more of a comfort feature (economic impact is also there but probably a lot lower than some would argue, given there are also mobile networks) whereas discouraging people from making great and bold business ideas and putting them into action can become a strong inhibiting economic factor at some point.
This is what they were concerned about.