I think a mainstream way of seeing things is that there’s rational agents and non-rational agents, and they behave differently.

I.e. a lot of economy discusses how a rational agent would behave. But economic schools also recognize that not every human is a rational agent, and that’s what advertisement is for. Basically, advertisement is a way to part fools and their money, i.e. give the money to more rational people instead. This is also partially justified with the philosophy that the world would become a better place if all the money (and therefore power) was in the hand of rational people.