The thing is that most people that receive that large amount of money feel like they can do it again, which is almost impossible, and continue gambling away their earnings.
They do that because they have won a big win and think that luck is on their side and thus the greedy thought of winning again appears by itself, but they are not aware that luck only comes once.This is a big mistake for gamblers who have won bets and this kind of thinking should have been pushed aside.
Quote
Casinos now this, so they of course invite you back, treat you with VIP status, etc, because they want their money back 
Actually, I actually assumed that this was a mutualism or mutual benefit even though it was actually the casino that benefited the most.Impressed to be used, but at least from both sides can get their respective benefits.