Thank you very much for your feedback. Building a great product that did not have variable usage costs that allowed for a generous free tier was my primary motivation for undertaking this project. While there is a need to monetize, I also believe there is a niche for an app with a more expansive free tier than exists in the space currently.
Only using the OFF database would be untenable to me as an end user. I think most people do not want to know or care about where the data is coming from, they just want it to be accurate and easy to use. I've listed the usability reasons here for why I can't offer that how I want with only OFF (and that's no dig to OFF, it is a fantastic project, and a primary motivator for this project and its license structure).
Some kind of fall-back mechanism would be nice, then, maybe? As someone who does indeed want it to be accurate, I would prefer to use OFF for any food which exists within their database, since it tends to be much more accurate (and maybe fall back to "AI search" if I want to look up "apple" or whatever).
I understand that most people probably consume more whole foods that might not have the cut-and-dry numbers on OFF. It just does feel like a big lacking feature to just categorically exclude OFF, if I wanted to use it.