First if all, you're not wrong. Depending on the financial risk in play, the anxiety and trust get tossed into a tizzy.
When I say financial risk, if I'm buying a car, we all already know that that's a whole racket. Buying a house, even bigger $$$$ involved. Buying a staple commodity, like a loaf of bread? Meh, it's no biggie.
One big factor in play is our emotional side.
I'll make a suggestion here. Feel free to ignore.
There's a book by Dr Robert Cialdini on persuasion. From what I recall, he got into learning how humans react to certain things, because he felt that he himself was duped into doing/buying things that he later realized he wished he hadn't done/bought. He wanted to better understand the process so that he could be more aware and less vulnerable to the grift. He ended up going into psychology and... well, specializing in the subject.
One sec, there's a website that gives a nice intro to this: