It's strange. On one hand banks and payment processors have been shown to bow to public pressure and turn away money in exchange for a little PR, but on the other hand banks also have no problems working with terrorists and cartels which are very much legally risky.

https://www.forbes.com/sites/afontevecchia/2012/07/16/hsbc-h...

The financially risky stuff they're usually willing to take on too, but the folks providing the service usually find the associated interchange fees unreasonable.

Exactly. Companies like CCBill specialize in high-risk transactions and will handle anything legal, but your fees might be as high as 14.5%!

https://ccbill.com/pricing

So they why do payment processors (paypal in particular) avoid firearms stuff? That's big business and the consumers involved pretty much all have discretionary income by definition. You'd think they'd be all over that.

Because gun purchases are a high chargeback risk; this is explicitly the reason that PayPal gives. I had a colleague of mine have a debit card stolen from them and then used to try and purchase a handgun. Given the criminal utility of a firearm purchased under a fake name with a stolen card, I doubt this is a rare problem.

(PayPal also cannot be used for cigarettes or porn, so they have a policy of avoiding what they see as high risk items, including items regularly handled by other card professors)

On the flip side Amazon will sell all kinds of firearm related accessories, just not the firearm itself or ammunition, presumably because they're not actually a FFL and can't handle the legal requirements.