Porn-related transactions have a higher than average rate of chargebacks. Maybe post-nut clarity motivates people to say “wait hold on I shouldn’t have spent that money, I must’ve been hacked.” Or maybe it’s people saving face when confronted with a transaction log from their spouse or other family members. Or maybe it’s just the type of transaction that actual card fraudsters gravitate towards, so that there really is a higher percentage of unauthorized transactions.

Gambling-related merchants also have a similar problem with payment processors. For many of them, it’s just straightforward business concerns, not any kind of ethical issue in itself.