when it comes to sports betting there is no house advantage, there is only the probability of winning from our decision.
Wrong. I guess you are a newbie in the sports-betting area. The house makes money from sports-betting through margin or juice which varies based on the sport, market type etc.
Some sports-betting sites charge high margins(Stake etc) while some charge low margins(Pinnacle etc). Betting exchanges charge zero or negligible margin since they earn through commissions on the bets.