Why would you want to use a provider, that resorts to shady practices, especially since there are a lot of alternatives out there?
Generally, you don't want to award people/companies that don't respect you. I'm not saying that you shouldn't re-evaluate them in the future, but they will walk away with the wrong lesson if you just start throwing money at them.
If you view it through a paying customer lens instead, then all you see is a paying customer who chose not to pay their invoice and might get sued. There's nothing strange about that.
All of the problem here was with the transition from free trial to paying customer.