Unless I'm making a mistake someplace, Digital Ocean includes 1TB egress to the internet from a $5-per-month host. On Google Cloud Platform that egress would cost $120/month by itself.
One thing folks like about AWS - you can actually know what you will be paying and there is no fake / hidden limits.
That's my somewhat outdated experience wasting a TON of time on this idea ages ago.
Give them a warning if you're going to spike your bill that high, but there shouldn't be any fake/hidden limits.