The gambling site owner have to earn money through the house edge, so you can't expect there is no hous edge.
That is exactly what we offer. We offer 0% fees on all sport bets:
https://www.fairlay.com/event/category/soccer/ Since we don't take a position but instead user bet against user the average user has an expected value of 0. If your bets are better than the average user your bets will make money in the long run.