people can ask what they want, the market will clear for an item if it is priced right, or, even if it isn’t
people without an accurate sense of what is a fair price for something they want to sell try to sell stuff all the time, for all sorts of things... cars houses boats bikes jewelry
key is - there are often equally uninformed people on the buy side too (or someone who is simply not price sensitive and wants the item) ... so for used audio gear, like all the other things, it just takes one buyer willing to pay