Basically instead of having some sort of website for your own sportsbook you are using this platform as a betting platform for your own bets. You start an event like lets say premier league game x vs y, then you promote it online, or tell the people you know at least and everyone gets together and bets on any side and whenever one side wins the other side pays for both the winning side plus 3% of all the pot in the middle goes to you.

So, let's say 50 bucks said x will win and 50 bucks said y will win, the x won so instead of getting 100 bucks as win they get 97 bucks and you get the 3 bucks as rake. Now, the website surely gets some too I haven't checked that but this has been quite common in sportsbook world. Not sure if there was any with dapp method but the idea has been around.