The last several garage sales I've had, the few people that stop seem to think everything should be free or next to it. Why is that?

That's interesting, I always thought the biggest hassle with garage sales were people showing up early, trying to be the first one there to buy other people's junk. I would never have one, I have nothing of value to sell.

All you have to say is no. Repeat as needed.

My parents had one years ago, they said never again just because of this.

Anything of value should be sold individually on Craigslist, letgo or offerup.

People sell garbage at garage sales and people expect everything to be cheap

I'm guessing because they are assuming that what you are trying to sell is pretty much worthless and that these items have no real intrinsic value.

Update: Boredom, idle curiosity, people love a bargain or the chance of picking up something that the seller doesn't realise is worth a small fortune. The same reason people visit flea markets and bric-a-brac stalls.

In this day and age, people assume anyone having a garage sale, rather than selling their stuff online is feeble minded.

Because they're taking advantage of the fact that garage sales prices are negotiable,combined with them being uninterested in fair exchange.

I only ever had a garage sale one time & never again.

I'd rather throw the stuff in the tip or give it to charity than put up with haggling idiots that want to talk you down to nothing