How can you bet nothing? I just tried it and I couldn't wager.
Also, I lost most of my last recent deposit not because I started betting high but because I took the risk on a higher increase on losing bet strategy. In fact, my biggest bets on the site have resulted in wins (two times 0.006 BTC).
Provably fair means you can check your own claims. Results are fair.
If you think they're scammers, why are you using their free sats?
I think what he meant was when he wasn't betting, they were not checking so everything was good until he started.