For example, take this recent question. The question is "Why are non-Western countries siding with China in the UN?", and the asker assumes that China has some kind of influence over non-Western countries that is making them side with China in the UN. In other words, these countries are siding with the UN in return for some kind benefit.
Why can't these other countries genuinely think whatever motion is under debate is just/unjust and vote accordingly? That seems like the obvious null hypothesis, yet people in general seem to reject that null hypothesis without a second thought. The linked question is just an example; there are many other examples around (example, example).
The only explanation I can think of is something I vaguely remember reading about in the context of magic tricks - that people need to be able to tell what the motivation of something is, or they get suspicious. For example, when the magician raises a hand to their ear, people are uncomfortable; when the magician uses that same hand to scratch their ear, then suddenly everything "makes sense" and the act ceases to be suspicious. Magicians exploit this effect to deceive their audiences.
However, I 1) can't find where I read that anymore, and 2) it doesn't explain why "these countries think [motion] is just/unjust" isn't also an explanation that makes sense.
