It's more than just the fun of the game.
Otherwise people would simply just play the free version of it.
It's all about the chances of becoming a rich person with a few coins.
Gambling should be a fun game that uses money. They must be able to use it as an activity in their spare time rather than making it a serious activity.
Otherwise, they don't need to use money just to play gambling games. They can use the free version, although it is less challenging for many people. They should not think about becoming rich in a short time because gambling is not a place to make money.
I wouldn't say that unless someone tries it first because there's no way that even if I think that it's a funny solution, there's still a chance that it might work you know. There's a hospice for dementia patients in Europe that created a fake bus stop for their patients because it helped them prevent the people afflicted by that dementia to not get lost because most dementia patients wander around familiar places and it just so happens that bus stops are the most familiar for these patients and yes it's not a long-term but you can see the effects of it which is the reduction of these people wandering aimlessly, that's the same with your solution of fake money, you might not see the benefit yet but it's there and there's nothing wrong with trying.
Using fake money to play slots or other gambling games in casinos can be a solution for those who want to spend their free time and don't want to experience losing their money, let alone losing large amounts of money. But many of them ultimately choose to deposit their money because they feel there are no interesting challenges so they intend to do so. They can deposit money to gamble but must have good self-control so they don't lose too much. But what happens is that many people use more money because they think it can increase their chances of winning, even though that is not true.