Exactly. People who save your details in their Address Book and click the "Sync your Contacts" when an app suggests it, are the loophole in privacy and security.
The only way is to have a separate set of email, phone numbers, for those family and friends who doesn't care about privacy and security, that way it is easy to dispose those information later.
Beyond that … if we truly want to avoid it … the only course of action is to not give them anything at all. Not a single email, not a single phone number, not even our home addresses.
I associate "The Krusty Krab" to fake/secondary/tertiary/spam profiles. People I know personally and those I was able to confirm as legitimate profiles doesn't use that or any other fake information (or just leave it empty most of the time). I only see such fake information in accounts used to advertise their business in someone else's threads.