All the permissions models are flawed. IMO Marshmallow actually makes it worse. They have permissions groups so, if you request access to Play Games accounts to

All the permissions models are flawed. IMO Marshmallow actually makes it worse. They have permissions groups so, if you request access to Play Games accounts to reduce the login friction the app asks you for access to Contacts. When a user opts out they get a painful login process. The real answer is for Google to stop asking the user for permission on the group and instead ask at the actual permission level.