mOgliE is addressing a serious point that I have noticed in the past, but didn't want to comment on.
These images (which I see on twitter every few days as well) makes it look like it's really common for gamblers t owin huge amounts of money. In the description, it often says stuff like 'this guys showed us how to turn X amount of money into Y amount of money, which is often not true since most gamblers need to make a huge amount of bets before they even hit that big multiplier.
If those ads where meant for little kids I would agree with your concern. But actually they are made for adults, who understand that normally ads tend to exaggerate things. I would compare them to the Coca-Cola ad below:

We all know that not every time we open a Coke we become instantly happy, and yet it is permissible to make such ads because we are supposed to understand that this is just an ad, and our happiness is not guaranteed by drinking Coca-Cola.