That's nice, but I'm not here to argue for one viewpoint or another, I'm just trying to explore the complaint that originated this thread.

Difference being you're still in full control of that data, can delete it at any time, and Airbnb the company doesn't have direct access to it.

They're not told it's there, there is no tool for them to view the data, to see what kind of data is there, or even delete data short of deleting the entire apps data. Airbnb the company can access it at approximately any time by pushing out an app update.

Legally you may have an argument, morally I don't think there's much of a difference. I would certainly not be pleased to find out an app was doing that.