Is it possible that those people have the email addresses you used for your various Facebook accounts in THEIR address books? I had something creepy like this happen, where FB recommended that I add my boss (despite me having ZERO connection to my work on my FB account… I don’t mention I work there, I don’t have any of my colleagues on my Facebook account, nothing), but my boss has my personal email somewhere in his various address books/contacts lists, one of which Facebook has access to, and voila.
