Earlier quoted context omitted.
In the past I built a few things on Google App Engine. Honestly one of my greatest regrets in life. I ported a few to PHP so I won't get screwed again when I need to change hosting provider. Still need to port some and am dreading doing it but it will be for the better.
It's a shame companies, especially large ones with strategic architecture teams who should know better, haven't identified the short term cost savings of using cloud provider specific services is not worth the long term cost of vendor lock in.
And really, it's not a bad trade - financially. But it will frustrate your eng team, for a bit - especially if you don't actually get the revenue stream going.