It bothers me too. I've learned that listing something for free on Craigslist attracts the people who will demand they you wait for them to drive 4 hours your way or complain that it's not in perfect condition. But listing a table for $10 instead makes regular people think it's a great deal while filtering out some of the hoarders.
I do the same, and then will just tell the person to not worry about the $10. "Really, you sure?", "Yeah, I'm just looking to get rid of it, but if you list it as free people treat you like crap and often don't actually come to pick it up." I don't do this often, but every time the person has understood exactly what I meant.
