Allow higher stakes (100,000, for example) that yield more antifreeze scoops. Instead of limiting people to so many antifreeze scoops per day, limit them to receiving so many rewards of antifreeze scoops per day.

By way of example, if a 50,000 bet was worth 2 scoops, and you could be rewarded ten times per day, then you could earn up to 20 scoops per day. If you stuck to 10,000 or 25,000 bets that each grant 1 scoop, then you could only earn 10 scoops per day.

Also, have the dealer take the pot on a tie instead of tampering with the cards. If you go by Vegas rules you’ll sink more money out of the economy than gets added, and allowing/promoting huge bets helps that along.