Players are not necessarily required to show ID to get their winnings in online casinos. Online casinos do not work like land-based casinos that will always ask for ID when working with players. Some online casinos might ask players to upload a copy of their ID, and they might not pay out any money until they have seen this proof. The casinos are trying to identify people who might abuse bonuses or have multiple accounts, and that is the reason they have an account where they might want to see a copy of the ID. If players do not have a valid form of ID, they are likely not old enough to be on the site, and that allows the casinos to weed out people who should not be there.