Are they a thing in America? It's always struck me as odd that the garage sale seems to be a bigger concept in a country that's so geared towards customer service, since the customers actually have to make an effort to drive around and find them.
That strikes me as funny!
Yes, we are very customer service oriented.
However, we are also "live in our cars" oriented. So driving around on a Saturday morning is pretty normal. The idea is that you're driving someplace, you see a sign for a garage sale, and you decide to stop, on the spur of the moment. As opposed to making a plan to actually go to a sale.
Now, of course, the vast majority of garage sailors (as I call them, me included) make plans to go sailing in advance. But you know, sometimes, I am
on the way somewhere else, see a sign and stop.
There are definitely community garage sales where lots of households gather in one spot, usually a large parking lot, and set up shop. No admission is charged and there's no fee to participate (AFAIK) so that's sort of like a car boot sale.
Those look more like this: