This can only happen if you explicitly allow an app to get data from Google.  And you can do a "security check" with your Google account where you see each external application and what data you have given it permission to see ("apps with access to your account").  The first time you log in to something like Academia with your Google account you are asked how much you want to share.  Normally, it's just your name and email account, which is what you want to share anyway.