Most times, the reason we fine poor person more in a casino hall is because, the rich are mostly based on online gambling with their mobile phones or PC but the poor, not having free access to this things would want to make use of public casinos. It's true if they have spent those money on a cheap altcoin usually meme that give a x5 or 10 it would be been a good start for them rather than playing gamble and looking irresponsible, they both are based on probability, but the reason gambling is more preferred is because of the quick result it gives.
It really depends on the casino you are talking about. There are many land based casinos where only rich gamblers will attend to, because the minimum bets accepted are already too expensive for an average gambler. These are wealthy casinos built and destined to provide services to the richest gamblers, so the environment is luxurious and heavily protected, employees well trained, food and drinks offered are of top quality.
Meanwhile, I guess the poor gamblers are the ones who prefer online casinos. Everyone nowadays has a smartphone and internet connection is available everywhere. Furthermore, these online apps accept minimum deposits from 1$ on or so, directly from and to the account of the individual. I've already seen many humble youngs who work for cheap wages gambling on such apps during their free time with very low sums of money, expecting to grow it into something considerable, maybe to purchase a good they were looking for since a long time, or to proportionate something for their girlfriends.
Proportionally to the total income of each of them, these poor gamblers are risking much more than the rich ones, and that is a big issue in my opinion, because it will prejudice the thriving potential of these individuals on long run, if they aren't lucky enough to hit some nice winnings. For the rich ones, on the other hand, it won't make difference at all, since they have abundant sources of income to replenish the amounts spent with gambling each new month.