It could be fraud, but I've also wondered if the two PayPal disadvantages were simply there to encourage credit card payments. For the volume they do, if their merchant account has even just a slightly lower rate, it could add up to a ton of money at the end of the year.
I deal with a retail site where it's not advertised for that reason, but it is occasionally accepted in some situations.
Kinda like how you're not allowed to charge people extra for using a credit card (or PayPal for that matter), but there's no law against giving cash discounts. Not much different than saying, "We won't charge you .4859% extra for using PayPal, but if you do use it, we won't give you a $97 discount."
I know there's plenty of PayPal fraud out there, but then again, credit card fraud was around before PayPal even existed.
I should probably add that if that's why they do it, I don't consider it greedy or deceptive--I think it's smart and don't blame them. If they're paying a lot more to accept PayPal, then it's nice of them to continue accepting it as a convenience for those that have no other options--even without the promo codes.
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