Can't Someone Just Sit At Home In This Country Without Being Offered A Job?

It's one thing to get telemarketers calling during the day, but lately my phone has offered up a new twist. During the past two weeks, I've received two calls from employment recruiters (or headhunters, as they refer to themselves as) asking me if I was satisfied where I was working, and if "something came up" would I like for them to call me. Of course, the jobs would be in the same field (transportation engineering, for those not paying attention to my life), and most likely the job would probably be in the GTA. Not that they had actual jobs available... they just wanted me for their files. I just replied that I'm quite happy where I am (which I am) and they shouldn't bother. The thing I'd like to know (and probably should have asked) is where they got my name and number? No matter. Besides, if I was to change jobs, it'd be something really different... and cool.