Yes, and how about iMessage and FaceTime that require email addresses in contacts to work? And also the 3rd party sites that rely on Facebook OAuth API to identify users based on emails (they could use uids, but I'm sure some are still using email).
http://www.apple.com/ios/ios6/#facebook
(Click the "Contacts and calendars", and see that contacts can have multiple addresses, even with Facebook sync.)
Do you care at all if it something Androidish? Something from MS? From anyone except Apple? If no, then shut your hypocritical mouth.
It would be great if someone would check this, though.
That's surprising.