This thread reminds me of a pet peeve. People who leave their garage sale signs posted way after the sale is over! So I waste gas and time looking for the sale, and it was two weeks ago. I think that should be considered littering. I also thing it brings extra noise, traffic, etc to their neighborhood.
I have figured out the yard sale lingo: "HUGE sale" means it is going to be a lot of baby clothes and toys (not interested). "Estate Sale" means there might be some good things there but usually it's old stinky stuff the kids don't know what to do with, and you've seen this stuff a zillion times before. The best sales are "Moving Sale". That is where you get nice items at a good price because they are moving, and don't want to pay to haul them, and don't know what else to do with them.