DigitalOcean simply does this at a later stage and will then just cut you off, Hetzner is doing it from the start. Their obligations aren't so different, they just approach this differently. It's the same thing with Stripe, it's cool that they just let you sign up and process transactions but at some point they will look at your business and if they don't like it they will just cut you off.
Also Hetzner really doesn't care much about individuals as far as I know, they mostly do business with other businesses and that's where the money is, their business is not designed to handle millions of individual users, DigitalOcean might also simply have a different strategy there.