The maximum of single bet is $750 on Roobet, I think Foss is buy the $150,000 bonus buy because based on the history, he's wager for $150,000 to make $$9,253,350 in Ethereum token, you can check it on Roobet site.
Foss is now actively gambling on Roobet, maybe he's an official Roobet's streamer. There's a site named Roobet Rewards
https://twitter.com/RoobetReloads which is Foss is the one who promoting it and there's his referral link there.
wow, that was a crazy win!
I haven't visited the site for a few days and after reading your reply I was surprised by what Foss did when he bought a $150k bonus spin, that's a huge amount for a slot game.
but for me Foss really deserved that big win in the game Wanted Dead Or A Wild. this game is at the well-known Hacksaw provider, one of the high volatility games and usually those who often bet on that game are rich gamblers or high rollers.
because Dead or a Wild has very high volatility which has the opportunity to get big wins. but it requires a very long spin to hit the big win that will get. so gamblers must continue to be patient doing spins there to wait for the big hits to come out and require a very large bankroll.
so it was only fitting that Foss got the win.