With some of the large companies, blacklisted is a real concern.

eBay is one known example.

I've heard the same for Amazon (forget if it was retail or AWS).

It's cheaper to lose your business than to have a proper human review every complaint.

I've charged back amazon over retail issues that they did not deem worthy of providing me a human to interact with.

It whined about it for a bit on their site but eventually just gave up. Works normal again.