With all the prop bets, multiple, alternate and money line bets on sporting events. Would it be possible to create a perfect hedge? whereas you would create a situation through the use of the different types of bets that can be placed and make it so regardless of the outcome you could make a profit?
It's obviously impossible due to house edge, even if you use different bookies.
Bonuses, rakeback and difference of odds make this possible. They are rare but they do exist.