see: Brexit

As in you underestimate what people will do for the power over others.

Even if it's not misinformation, you can't expect every voter to inform themselves on every issue to know what the best decision is

As in not giving enough credit to politicians?

Uh, you give people in general too much credit. And at the same time you give too little credit to some of them who are willing to go the distance...

Do the people not already face misinformation from political parties? Maybe I am giving society too much credit.

It's already the case that the majority votes against their own social and economic interests. Doing that on every issue is a scary thought tbh