Netflix is hosted on AWS to name just one such instance. I have heard that internally the customer names are obfuscated, including other Amazon services. Indeed it would be a death sentence to prioritize themselves.
I understand not wanting to use SHA-1 now for security reasons, but is it still an OK practice to use it as a general hashing function for a uuid/data checksum?
Didnt' China try to do this a few years back but was shutdown for some reason? Also, this would double as a great military weapon so I am sure that is being assessed as well.
Also there really is no one AWS, each region is its own (Now more then ever before, where some systems weren't built to support this).