[DaKnOb]

There are some providers who "buy" their blacklists from other companies that specialize in that. They essentially get a list of X IP Addresses / Subnets and they blindly block them. Providers compete to generate the "largest blocklist" with "the most bad guys", and therefore end up adding any IP Address they can find. Tor has been used by criminals at least once, therefore any address related to it must be bad, right?

[pricechild]

Neustar is one of those providers and they obviously don't want to talk to anyone.

I'm not sure who Amazon Video uses, but they also block relays, not just exit nodes.