Shouldn't the platform owner (e.g. Facebook) make sure that no intrusive apps can connect in the first place?
A great feature from Facebook would be time-limited access; i.e. Quora can access my Facebook info for 24 hours and then all permissions are revoked. Although, unless the app is using long-lived access tokens, they can only access your FB info for a few hours after an active session -- so if you haven't logged in recently, the app can't grab your data.
When "intrusive" conflicts with "making money", guess which one wins?
But seriously: Haven't found an app that was worth a damn to enable in the first place.