It has been mentioned before but let me say that I remember watching to Casino Royale in the cinema (too many) years ago when I didn't know the rules and thinking: woah! this game is super interesting. I think that this is the time I was most impacted by a movie in terms of gambling. There have been others, like a few ones where the protagonists win the lottery and their lives change (normally to worse), and others where gambling appeared somehow but was secondary. But in the case of 007, the glamour surrounding the game really made a difference.

BTW, the title of this thread refers to Pop Culture but the OP asks about movies. Won't we talk about other disciplines, like music, or paintings? The latter reminded me of these famous paintings, but they are too old to be considered Pop.