OMG some guy has signed me up for EVERYTHING from Home Depot to every dating site, to porn sites to cheating sites. It's absurd. I get daily emails from these services still even with unsubscribes and blocks. They're insessant.
Linkedin is criminal in this department.
I don't really like email alerts for social media as a concept anyway, if I want to hear what LinkedIn has to say I'll look at LinkedIn itself, it has no business injecting itself into the rest of my life via out-of-band methods like email.