What the hell is wrong with Craigslist People

I have had similar issues with no response from sellers, it is frustrating. Most of the time I sell something, the potential buyer asks me 20 questions and they are usually already answered in my ad.

Me with 4 free 16" summer only almost to the wear bar tires listed off the wife's car from when I put on new tires before last winter:
Dude calls... his first words instead of hello are... "Where you at?!". I reply "Where are you at?" he says "I am by Office Max". I say, "There is no Office Max within 60 miles of me man." He says: "I am in Sioux Falls and really need those tires!". I say "Well I am two hours away in MN." he goes "Oh, ok well never mind." and hangs up. This was around 8pm on a week night. I had the location and map in the ad as well. The person who finally did come to get the tires asked, "how much?" I politely said, "in the ad I posted free, they are free.". He asks "how much tread? Good enough for winter?" I say "No, they are almost down to the wear bars and summer only, and they are free, just like I said in the ad." he asks "Will they fit my Grand Am?" I reply "I don't know, I have the size listed, that is for you to find out.". He finally got the tires and I was happy to be done with that stupid deal.