Last weekend we participated in a garage sale with some other members of our family. Unfortunately it was mostly a bust. Our gross sales were about $150, and that was split among four households. I'd estimate that we sold about 1% of the goods we offered for sale. It was nice to get rid of the stuff, but still, we were disappointed.
I have to wonder what went wrong. Very few shoppers came. The ones that did bought a pretty decent amount of stuff, so I don't think there was a problem with the goods or the way we laid them out. I think the sale was well advertised and there were no weather problems, so I think it was simply lack of interest in garage sales.
My hypothesis is that three trends are killing garage sales.
The first is fuel prices. The value proposition of a garage sale gets a lot worse when it costs a few dollars to drive to it. So I bet some garage sale veterans are (rationally) choosing to go garage-saling less.
The second trend is the rise of eBay, Craigslist, and Freecycle. All three are more convenient than garage sales since they let you shop for precisely what you want instead of sifting through a pile of everything. Most people probably prefer Craigslist and Freecycle for nearly-free stuff, and eBay and thrift stores for more valuable used items. That leaves a very narrow gap for garage sales to fill.
Finally I think this is part of the broader trend of Generation Y's preference for electronically-mediated interactions. Craigslist and eBay are fully Web 2.0-ified, but a garage sale is a purely in-person, face-to-face, analog affair. Our sale's customers support this idea, at least anecdotally. Almost all our customers were middle aged or older; we only had one group under the age of thirty, and the neighborhood kids ignored us entirely.