So is mine but think about it.
You register with facebook using
dummy@dummy.com.
You decide to stop using facebook.
You get emails asking you to come back to facebook with your registered email
dummy@dummy.com
You change your
dummy@dummy.com password in a pointless attempt to stop the emails.
Facebook doesn't care what your
dummy@dummy.com password is, its still going to get sent to
dummy@dummy.com