LOL Exactly, it's not that people are idiots exactly, it's that particuarly young people have a very large need to be noticed, I could go into the whole hormones etc, but really, what it boils down to is establishing a role in society for themselves.
I put part of the blame here on Media, there is a projected image in the Western hemisphere that if you are not 'Someone', you are 'No-one', if you don't wear 'this', you aren't 'someone' etc. That means people like Paris Hilton, who is in the public eye, gets used as a role model, she profits from it usually, she's obviously 'successful' (in truth she is rich, not successfull, her father was the successfull one - and yes, there's one to many of something in the word 'successfull') and so people try to emulate her.
Thing is, when you are a Role Model, and she certainly embraced the role when it was going in her direction, some strange rules apply to your life, shopping will earn you money because it's good advertising. Breaking the law will get your ass kicked, because the legal system understands what is known as 'parent power'. Any lawyer can argue that, as a role model, Paris should be more expected to set a good example to the children of America. It is an undefendable accusation because it is 'for the children'.
Did she choose her lifestyle? Not as such, I don't think she's so much stupid, I just think she's never had any need to learn, hopefully this will come as an education.