Please. People have always been gullible, it's just that the scams have moved to more lucrative enterprises.
It is a problem of basic finance education which should be part of the school curriculum. People also buy a lot of stuff they don't need or include false claims because a banner told them to.
I don't know any government funded school... do you? Beyond this, people need financial knowledge to make better decisions since finance skills are required on a daily basis in the modern world.
The obvious answer to your first question is: It has severe detrimental effects to our society, and we'd all be better off if people were taught the basics.
Not sure SEC is a good example, since they are a corrupt organization focused on prohibiting class mobility. Their propaganda works better than ads on the same people.