$500 is very huge amount for people who are living in a third world countries even the decent paid job will be less than $500 as far I know. Anyway the budget depends on our affordability but make sure that the amount we are spending worth it by enjoying it rather than getting addicted to it.
I can confirm this, the minimum wage in my country is around 10 USD so I agree that 500 USD is a huge amount of money, the budget also depends on the place that you're in, for example, in my country, it's much cheaper to gamble than in Las Vegas. Online gambling is a different story though, everyone is equal on that one.