These things don't annoy me at all.
Random invites from (A FULL NAME)(SOME NUMBERS)@hotmail.com get rejected, blocked and reported as spammers every time, unless the person told me they were going to add me. So if they annoy you, it's your own fault for responding or even allowing them to contact you - congratulations on being trolled by a computer.
I've got this in excess of 12 times by alts of some fgt. One of these days, I'm gonna post the address they give (paris12@hotmail.com i think) and post it on /b/ and tell them to go crazy. C: