Docker hosting related

It seems that i'm missing some could fundamentals: I need to run ~10 docker containers somewhere - and because i do not expect any traffic on them i was looking for the cheapest hosting possible and i stumble uppon the following - there is no actual pay for demands hosting. No matter what i will choose the first step is to choose vps resources and reserve them. I had big hopes for amazon ECS but at the end it looks like automated EC2 service with some "recipes" for running containers "automatically". So am i missing something or actually there is no pay for demand hosting available ?