At one time, boxing was the most popular sport in America. That changed. As Gregg easterbrook likes to say, there is no rule that the NFL has to be popular.
This is a serious issue for football. It has to figure out a way to eliminate concussions or it will be marginalized as a sport.
Naw ... boxing has just sucked the last 20 yrs. Otherwise, they would have been required to wear helmets. The sport lacks personality and competition..
I read an interesting article on a "economics of sports" blog. The failure of the NFL will begin with parents not allowing their kids to play peewee. The NFL needs to jump on this, if it intends to continue as a viable franchise.