OK so this is only a Perl meditation insofar as Perl powers many websites where this issue is relevant. The problem with facebook connect is not with every reasonable site offering it but that users become habituated to it and can fall into a trap at some time like this:-
The bait will be some benefit of sufficient attraction to encourage people to register on the site. The option "connect with facebook" will be a trojan. All too easy. The only way to avoid the trap for most users is to never connect with facebook as a security policy.
Or is there another way to help them?