I think spire.io is more geared towards people making new applications. If you already have a working backend, keep using it. However, if you are making a new web application, you need to pick your battles; do you spend your time writing server code and setting up a server, or do you spend your time writing the actual application? It is a reinventing the wheel thing. You want to spend your time writing the parts of your app that are DIFFERENT and actually core to your application.

These services exist for things like... game high scores, not real data that makes anyone any money.

They're for "incidental" data, rather than "valuable" data.

But I agree with you: you're setting yourself up for massive failure relying on any of these things.