re: People who try to sell stuff online for absurd prices

You are 100% correct. All of those jackdicks should contact YOU to determine the correct sales price. AND you could CHARGE them a fee.

Problem is, How much do you charge?

Some people have no idea how to price things, so they just list them on the high end of the market and wait for somebody to make them an offer they deem acceptable. Think of it like this: You have an item that you think is worth anywhere from $100-$200. This is based on other listings you've seen, your original purchase price, condition of item, market demand, etc. The average Joe has no idea how to measure all these variables, so he'll list it for $200+ even though his particular item is closer to the lower end of the spectrum. But by listing it at the high end, he gives himself bargaining leverage with potential buyers. If he lists it at $200 and gets offers that are less than $200, but more than what it is worth at $100, then the seller profits by starting the listing higher. If he simply starts out by listing it at $100, then the offers are going to come in at or below $100. It's just smart to give yourself a better starting point.

I've volunteered in a couple garage sales where there is definitely junk listed way higher than it should be, but I'm appalled more of the scavengers don't at least make offers. I'll hear people say "Oh, I like this item, but $10 is a little too high" and then they walk away. Then offer $5 dumb arse. It's a garage sale, they probably just want to get rid of it

TLDR - Basically, most buyers will offer to buy at or below the asking price, so the higher your initial asking price, the higher the offers you should theoretically start with. If you think their asking price is unreasonable then either move on, or make an offer at what you think is fair and maybe they'll accept.