In all fairness, when the pros do it they are literally branding themselves and, whether all of us like it or not, are marketing themselves to earn money. College kids can't do that due to rules as archaic as the ark and the predisposition that the only people that can make money off the athletes' talents are everyone except the athletes themselves.
We can criticize (and I am one of those people who do...and I'm not fair because while I may love the Merton Hanks chicken dance, I think the Zeke elliot "feed me" move is dumb) but the reality of it is it is literal money in the bank. A guy can do something and then he winds up on a .com commercial or selling deodorant or something. I'd say if any of us went into board meetings and ripped up the quarterly financials and screamed "And that's the bottom line, gentlemen!" and then got a bonus for it every time we did it, we would do it too. Regardless if the hot secretary said we were a neanderthal for doing so.