If you are extremely rich and you can just gamble up to your heart's content, does the novelty of winning wear off? Like would you get tired of gambling since there's really not much risks because you can gamble with any amount and still receive little to no consequences?
You can lose the motivation for money, but there are other elements that aren't related to money, such as the feeling of winning, being better than others in the social aspects of the game, and status.
Money is a very important part of gambling, but it's not the only reward you get from winning.