accepting cryptocurrency is depending on jurisdiction a legal liability
people already are trying to use all kind of vectors to launder money, including steam
and cryptocurrency systems in general don't do the legal due diligence of a payment processor/bank
so you now have the problem of being partially responsibility to do that legal due diligence yourself and make your service more attractive to be abused as in money laundering schemes
but if things get worse they could consider creating a payment processor sub company, the issue with that is I think there are a lot of way Visa can mess with them in the US and it seems not necessary in the EU (as due to side effects of pushing/forcing banking payment system improvements you technically have a wide choice of alternatives to PayPal or Credit Card payment for only payment, it's just many solutions are niche so most sides don't bother for now (but things are changing))