Usually I don't open a mail unless I know ther sender so even if I was getting these mails I probably wouldn't notice it. However I have noticed that I get a lot (2 or 3 a day) om mails saying I've received an eCard from a friend, these go straight to the bin without opening as well but it's very annoying.
On an aside I got a mail recently from askaboutmoney stating I had received a PM from a member. I logged on here and no PM, I looked up the member list and no such member existed....strange????????