The problem with baseball caps is that they are not only very functional, but stylish (to certain folks). And they lend themselves naturally to advertising, with the ability to carry a logo. Some people wear billed caps purely for practical purposes, and others wear theirs because of social pressure or are just following their specific kind of fashion trend.
For myself, I have played a lot of baseball, and had to wear a hard hat for many years of my working career. So I'm loath to put anything on my head.
I live in a city, and most people wearing baseball caps do so because of fashion and their need to fit into their peer group. And the merchandising and fashion people know this, and make a lot of money from this avenue. Heck, why do you think LeBron James wants to change numbers? For merchandising, make more money.
One thing to always remember, baseball caps, despite all the advertising are not sexy. You will never find a sexy, sophisticated woman in a ball cap.
And if you do wear your cap backwards, make sure you have an even tan first.