> If I'm underage, but already have a payment card, the identity of the card matches my name.
And if a gambling site stops there and goes "LGTM", it's not the "union of {payment information, KYC}".
Union, as in combination of both.
KYC, as in "Know Your Customer". Looks like MitID is a thing that would be one way to do KYC? But I've only just heard of it, so belief is weakly held.