FWIW, in principle I agree with both points being made, but in practice I just didn't want to be responsible for following the issue and making sure it got reso

FWIW, in principle I agree with both points being made, but in practice I just didn't want to be responsible for following the issue and making sure it got resolved correctly. I wanted to hear "oops, leave it to us" and then stop thinking about it. Perhaps worth adding, I was/am 99% sure how the charge occurred, and that it was a Heisenbug from when I'd trialled Prime. So there was no question of punishing them for being a bad vendor, I just needed them to bounce the issue around until it landed on someone who could fix it (which is essentially what happened). I think the real root cause of situations like this is that social teams sometimes have more/better options for escalating issues than customer support does.