I think I last piggybacked on a sale that my neighbor was doing to get rid of some personal items. Didn't make all that much money, but did get rid of things that needed to go.
Two years ago some friends and I did the community garage sale to benefit rescue. We had lots of new items, I mean sweatshirts that normally sell for $65 and it was insulting to have someone spend 20 minutes looking something like that all over and offering only $1 for it. (The new items were hung on hangers on a garment rack with a large sign labelled NEW MERCHANDISE!) I really need to have another one but with a schedule of work, walking the rescue dogs, rain earlier in the summer, putting in the garden, canning, and being sick earlier this month, I just haven't gotten around to working on it. 
A friend of mine has a garage sale each year. He and his wife will put things out, everything clean, grouping like items together. They will also put ice in a cooler and have bottled water and sodas, coffee, some packaged snacks. (They mark up slightly on these items to cover the gas.) But, they mark the items for the garage sale at prices where the stuff will move, since that is the objective. If things don't sell, they will box up the newest items that have only been out this sale and those will go in the garage for the next sale. Other items will go to local thrift stores. They have other people piggyback with them, everyone marks their own items and those that are able will stay throughout the sale. He and his wife do their sale on vacation time, it's kind of a party atmostphere with lots of talking to shoppers. Their sales are always very successful, and you never know what you will find there: collectibles, old pots and pans, furniture, always that "something for everyone" type of sale. Then, they have a box in the basement, and as they clean throughout the year, items get added to the new garage sale box. When they get that appropriate mix again, then it's time for the next sale. I should probably add that both are adults and, although they do not have children, some of their friends do. But it seems to me they don't put out much in the way of clothes at their sales, rather donate or consign them.
There is usually someone in my family glad to have hand-me-downs, especially when I was buying nice things for the office. I am now closer to retirement and more frugal in my choices, although when I bought new items, they were always on sale.
I think it's a toss-up. People have less money, have a set price in mind that they will pay for something, and will haggle.