Earlier quoted context omitted.
Sounds like a completely legitimate use though. Hetzner were widely telling people about that 20TB limit, so why would they be surprised when people use them as CDN boxes?
Where's the surprise? It's the classic business 2-step - drum up interest with "too good to be true" features, then cut them back. The marginal customers who need those features leave (and are too expensive to keep), everyone else is used to your product and stays.
I prefer to assume naivety over malice/negligence.