I have run a personal web server open to the Internet. But a good 15 years ago, I actually tried running a public website. It lasted for a few months, then they disconnected me until I called and agreed to turn it off.
I'm willing to bet your provider has something similar, enforcement may be lax, but it's not something you can count on.
That's great if true. However they have the catch all "non-ordinary use" clause. Obviously if you try to run a massive data center, they'll shut you down, which raises the question of where the cutoff is going to be.
The only reason they have this in the contract is so they can cancel your service over it, I can guarantee they're not monitoring this at all any more. If they wanted to block hosting services they'd block the ports on their side.
I have run a personal web server open to the Internet. But a good 15 years ago, I actually tried running a public website. It lasted for a few months, then they disconnected me until I called and agreed to turn it off.
I'm willing to bet your provider has something similar, enforcement may be lax, but it's not something you can count on.