They do. You can vendor lock a card and give it an all-time transaction cap. They've always had vendor locking but IDK if they've always have an all-time cap. I have run into the same problem GP ran into with someone running a test charge and failing the real charge, but I wasn't banned as a result, of course.

Yeah specifically when I signed up they did the a small charge then, I assumed it only ever do a single charge to check for the legitimacy of the card. If I ever wanted to do a paid tier, I would have changed the card details. But it was a week later that they did a second check even though I hadn't done anything that would incur a charge. The card I had setup with privacy was a charge once card that immediately closes after the first transaction is completed (including charges that are canceled.) So the second charge hit the card after the card was closed. At that point they decided the card must have been stolen and decided to permanently close my account with no recourse.

My guess in the end is they just don't care, I'm not the one that would be giving them lots of money, business contracts are. But they are wrong in the sense that I will never let any company I ever work for choose them if I have any say in the matter.

But there are valid reasons for it to get rejected - I have my limit on my card set to 0, so that in case the information gets stolen, I won't get any damage right away. And it happened a few times I went to get something and forgot I haven't temporarily changed it.

If your credit card limit is set to zero, I can see why a business with post-paid services would not accept that as a valid payment method.

I mean, sorry - again, bad wording on my side - you are true, but it shouldn't ban the card - let me repeat it later