Say what you want, but sports betting is different. It isn't mainly luck based like casino games, but requires skill. It's impossible to lose 500.000$ in sports betting, when you have A) a clue of the sports you're betting on and B) know the fucking basics of bankroll management.

Bookies make money due the greed and stupidity of their costumers and not because they are mispricing odds and gain an edge. I know a lot of people making money by betting on sports and their ROI ranges from 5% to 15%.