The thing with hunting 9900x is that you can be losing 50k-60k rolls in a row easily, and in some extreme cases it can be 100k rolls in a row without hitting it. Doubling your bet after 1k-2k losses in a row is a very dangerous strategy which can drain out your entire balance before you hit the target. Your friend was just lucky, and no way he can be used as a role model for other gamblers.
It's a big risk if you keep doubling up your bets while trying to hit that multiplier, though there are some gamblers who's willing to gamble and try their luck but not that many have that same level of capacity to take the risk, it's a huge amount and no one knows when luck will permits and hit you up.
I can understand them actually. It's very tempting to start doubling your bet after some point, to make all those previous losses being "not in vain". We all know that's a flawed way of thinking, but gamblers are known for being irrational from time to time. I do it sometimes myself, but my overall losses, even after hundreds tries, are less than $2. That's what important: do whatever you want, but calculate your possible losses in advance.
Wow, that's really a well disipcline gaming. If you have that capabilities and happened that you able to hit that big odds the money that will go to your pocket is very decent.
I was an aggressive gambler before but after losing a huge amount of money I learned my lesson.
Now, I'm only playing when I have spare coin just to relax out and try some luck.