Seeing that I'm today's world, not everyone is genuinely happy when they see or hear about people winning is enough reason to protect your winnings and sometimes Don't even share because you never can tell exactly who is happy with you and who is going to be that enemy you need to stay far from so they don't get a chance to unleash their hate on the winner such that in some cases it may lead to a very severe case that both the gambler and casino may not be able to contain.
I am a person who is very happy when a person wins at the casino, whoever it is, I like it when it happens, in fact I always recommend to any person that when they win, they take out and withdraw their winnings so they can enjoy them, so because of this it can be deduced that it is better to do things this way, of course there are people who think differently and they are respected, however when I have little money I withdraw it and if I spend it, even better , because it is the only way I see that it is worth playing, that way I see the fruit of my effort.
Also I am. I am very much excited when someone wins good amount. I jubilate with the person and I don't expect anything from the person but just happy with the win. But if the person is my friend then I will tell the person to buy me a drink to jubilate with him. But there are some guys that habitual to ask people that wins. There are some gamblers that are charitable while some are not.
It is a choice and personal habit. If the person is not good for sharing then he will not give out his struggling win to others.