My guess is it's simply a chargeback risk. It's the reason casinos and adult sites have trouble getting credit card processing and are charged much higher basic rates, even under the best of circumstances when the casino or adult site is operating entirely within the law in the jurisdictions it allows.
Punters run a lot of chargebacks on casinos, and people whose spouses catch a XXX video or game on their card statement will lie and run chargebacks too.
In the case of Valve, a lot of chargebacks would drastically increase the processing rates demanded by the payment providers for all transactions across the board, not just those related to adult games.
There's probably a great market opportunity here for a game store focused on adult games and willing to take on that risk.
Visa/MC still make a decent amount of money on chargebacks - the fee is $15 or so, of which the platform keeps a big chunk.
Often it's because of secret government requirements.
Compare https://en.wikipedia.org/wiki/Operation_Choke_Point .
Somehow, it's forbidden for the government to oppress pornographers directly, but it's perfectly fine to impose legal sanctions on banks who maintain business relationships with them.
This is the correct answer. There are many merchant categories, adult being just one of them, that are susceptible to high chargeback rates which result in payment processors banning them.
That's the problem though. The risk means the market for those riskier credit transactions is literally categorically not a great market. You think JP Morgan gives a shit about Japanese titty games? Hah. No. They care that these games get charged back way more often.
If there is a market opportunity, it's probably in a processor for debit-based transactions that are harder to reverse. But then that makes fraud harder to combat, and one of the reasons everyone loves credit cards so much is because consumers are far more confident to buy from random shops if they know they can always get their money back if the shop scams them.
So - this whole system's lucratively is entirely predicated on easy credit and low risk meaning low fees. Anyone who wants to play in the mud that's leftover by these companies taking the good business are inherently playing a low margin risky game.
Isn't it a little odd that Visa/Master isn't out there making that argument? Why would we assume them having the best of intentions of they aren't even willing to argue those intentions themselves?
Does Valve actually have a high risk of chargebacks? I was under the impression that moreso than other platforms, most Valve customers would rather go through Valve's own refund system. I understand that chargebacks is supposedly the reason for adult-only platforms.