Eating and what it brings can surely be the playground of Satan. Drinking and what it brings can surely be the playground of Satan. I'm gonna need some specific scirptural support regarding gambling? :-)
Specifically I'll admit that on gambling scripture is lacking. But generally it goes against biblical principles of lust, greed and giving to others. When you gamble what aren't you coveting someone else's money? Don't you desire to win the casino's money or someone else's money? If not why do it?
If you want to satisfy you sense of entertainment why not just play poker for fun? Or for chips?
Would Jesus go to Vegas and gamble even once for entertainment? Would any of his disciples?