It seems that unbeknownst to most of its users, since Patreon has allowed creators to post videos they have been dumping those videos on 'pro' level Vimeo accounts rather than hosting the content themselves (as any self-respecting publisher would do).
When Vimeo came calling to look for the payment for excess bandwidth that particularly popular creators used, Patreon just passed the invoice right on through to the content creators, some of whom have been notified that they have a week to pay Vimeo thousands of dollars or have all of their content deleted.
https://twitter.com/hate5six/status/1481500463317012482?s=21
https://www.patreon.com/posts/vimeo-is-holding-61514364