I would call roulette a game of chance. I would also argue that you DO have influence, over how much and where you bet, which can have a significant impact on how much you win or lose.
I would say that if it was made to be a game, and people call it a game, then it's a game. A chessboard and pieces could be a piece of art if it was called art and hung up in a gallery. But, if it's called a game and is used as a game, then it's a game. The context is the important thing.