Personally I don't know, as I use K-9 Mail from F-Droid. But from the viewpoint of an advertising company, keeping the option open to insert ads, even if they

Personally I don't know, as I use K-9 Mail from F-Droid. But from the viewpoint of an advertising company, keeping the option open to insert ads, even if they may not be doing so at this time, is in their best interests.