Hopefully, the Googster doesn't pull the rug out from under your feet and decide to deprecate whatever product(s) you are using of theirs. It is always something to keep in mind with using anything from G as a central part of your offerings.
Spot on. Fortunately, the underlying platform itself is independent of Google.
The Forms and Sheets add-ons are just customer acquisition channels, just like our Zapier integration [1]. These mostly use our API, and very little of our UI (mostly the scanner).