I have to admit - I *do* use Google Keep. Mostly because it didn't require yet-another-account, and somewhat because my workplace uses Google Apps anyway so it fits nicely.
It's a little to-do list app that runs on anything, stores my notes, and works when offline (provided you're synced as much as you need, of course). It does lists, text, video, even audio and doodles.
But it's by no means a critical service. It is, quite literally, my shopping lists / doodle app. Oh, must remember the bread.
So I wouldn't care if the online service went down.
The app would probably work anyway, even if I have to use it "unsynched".
And I wouldn't lose anything critical.
Quite why that makes them a $200m business, I can't fathom. That's over $10 per user. Have they paid that?
Just use Google Keep. It's only a shopping list, who cares about it to that point?