I mean you can accept it and still be on the hunt for a better job offer, no? You wouldn't lose any opportunities from accepting the offer.

Sure. Some may even hold multiple jobs (Overemployed movement).

Nit: you're never in that position in blackjack. You only double when you have 9, 10, or 11, but you'll always hit that anyway. Some bizarre casino could theoretically let you double Ace-10, but that's just getting greedy.

Anyway, you meant stay or hit.