I would go as far as saying that the hosting for such a service should be entirely sponsored by Microsoft.

He's a "Microsoft Regional Director and MVP" so Microsoft pays the bill one way or another. I expect that he has reduced Azure rates as well.

Regional Directors and MVPs aren't employed by Microsoft: https://rd.microsoft.com/en-us/about/

I have a monthly azure credit of $150 and some reduced pricing simply by having a ms developer subscription. I'm guessing Microsoft MVP's (in general, and Azure MVPs perhaps in particular) have extremely generous azure credits so hopefully he isn't on the line for the full amount here.

Would be even classier if the major cloud providers responded to customers calling out for budget limits for the past decade. Not many people want to risk potentially infinite costs.