Let us ask this question, Would a ref be more likely to make a call the wrong way out of favoritism that could cost him his job or out of economic incentive?
I forget the exact circumstances, but there had been a lot of money bet on one side, so the Vegas bookies would have lost a fortune. In the second half, it became obvious the game wasn't going the bookies way, and the stadium lights went out. They called the game. Vegas declared it "no game" and refused to pay.
Watching the NBA playoffs, it became obvious that Magic Johnson, Larry Bird, and Michael Jordan could have shot people and not fouled out of a game.
As to the NFL, I've seen some AWFUL officiating, but nothing to make me suspect a game was fixed.