I tried to sign up for Beeminder today just using my Google account, but it asked for permission to read all my Gmail. I said ‘cancel’ (there was no option for ‘no’) and the sign up failed. I signed up for a native beeminder account instead, but it was a little bit jarring to have that permission requested.
The Beeminder Changelog lists #439 from May 2012: Separated Gmail from Google as services you can log in with. Sorry if @bmndr was needlessly asking for permission to read your email!
So something seems to have regressed in the last six years 
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