well - I did that .... and changed the email address to a dummy account .... and still they send me almost weekly spam to the old address - "Why aren't you using FaceBook? here's a single link you can use to log on without a password" ... these bozos have no concept of security
Sounds like what has been happening to me. Except when I try to login to nuke the thing I get some error message about a database error and can't login. So the Facebook spam about new friend suggestions etc keeps coming. But since I have always marked it as spam it usually goes straight to the spam box.