Let me see if you can help me understand something. Yesterday I played a few hands, but only a few, about 10 or so, and I'm sure I got a cashback, because what I had left in my account was a round number and now there are more.
I don't think it's a bug, just an overlooked reward and pays off for those active is all.
Ok understand... this happens because there are not enough players during some hours but is not always possible

. Best trick is to check at the end of the hour and be able to understand if there is "enough space" in current rank.
Of course this is a good opportunity for people betting with a low amount and don't want risk too much.
Probably not worth it for the 1k or 2k rewards. As far as I can tell during the past week at least, wager the minimum bet on Blackjack, play about 10 hands and you're fine. I do double up on bets semi martingale so I guess it can become significant on one losing streak but anyway, no pain no gain, usually is the case lol.