It completely depends upon the website we choose gambling because there are many websites where they will allow to gamble with BTC, ETH, LTC, Doge but from the people i used to hear that most of the people will Dogecoin for gambling because of it's speed. The other famous coin is LTC, which is another one to gamble frequently.
Most crypto gambling sites accepts BTC, Eth, and LTC. But I think so many people just prefer dogecoin not just because of the speed but because of its affordability. The truth is no body wants to lose their BTC, gathering BTC is not easy, and I don’t think anyone would want to gamble that, so it’s better to go for something cheaper, the goal is to have fun and at least make back something regardless of how little.
BTC, ETH and other bigger crypto currencies are for big time gamblers who have gambling as their profession and a major source of income not for someone like me who only plays for fun.