You're missing the point by a country mile. It's not about the money - it's the about sport of it, the competition of it. These guys make millions of dollars but yet they gamble against each other on flights all the time, because of the sport of it. There is an old saying that if teammates are fighting, it's usually over one of 2 things: a woman, or a gambling debt. And yet these guys make millions of dollars.
As for not hating the opponent - maybe not in basketball, but in football, you are trying to rip your opponents' heads off play after play after play. These guys are juiced up and popping amphetamines to get them even more hyped. Hell yeah they want to injure their opponents.
People are absolutely right when they say this has been going on forever, and it's most definitely been going on other locker rooms besides the Saints. Not saying it's right...just saying that it's out there...