I think the gullible take is to imagine that the wealthy and powerful maximize their gains in an unstable system. They don't care about stupid people, but they

I think the gullible take is to imagine that the wealthy and powerful maximize their gains in an unstable system. They don't care about stupid people, but they care about the instability that comes with people getting taken in by scams or bad deals. People who are currently at the top of a power structure have an interest in stability. One way of doing that is allowing people further down the power structure to profit in a limited way from the system. This both won't change anyone's relative position, and is a genuine improvement for all parties. My other critique of "rules are about protecting the rich" is that the counter-factual of no rules does hurt the rich, but it hurts everyone else as well. It just doesn't seem true that striking down rules against manipulating markets is helpful to the non-rich, so it feels like cutting off your nose to spite your face.