Look at her username

That makes zero sense

Why the hell would you expect a sports bra to crack a guys ribs? They make them in larger sizes, it's not like a guy would buy one for a woman 6 inches shorter and 50 pounds lighter than he is. What I am wondering is why a man who plays football/soccer would need one since it is such an athletic sport.

Uh, because women tend to have different proportions than men, and men trying to wear sports bras tends to result in cracked ribs as a result. The question of why isn't as much of a question, because pectorals can become enlarged in men who exercise heavily, to the point of looking like breasts.

Sports bras are made of spandex and elastic. They don't crack ribs, I've never heard of that before. In double checking it before posting this, this FML is the fourth result in Google and all of the other results are talking about how to deal with cracked ribs when you have to wear a bra. It doesn't even look like a conspiracy theory some people have, I have no idea where you got that information. If OP is worried about her teammates pec making her look flat, she should hit the weight bench and get some of her own.

Probably people that are pissy that a woman is playing (American?) football on the same team as guys.