Is it everyone in Australia named Bruce? 🤣
Could be people that sign up, but can't figure out how to use it. Or people that sign up just to follow others, or join groups etc.
Or duplicate accounts. It is quite easy to accidentally create a duplicate account, if you try logging in with a different email address. Even something like gmail.com vs googlemail.com. Or if you try logging in with Facebook, that would create another separate account.