Why do so many sellers take offense to offers on their listings?

No need to go into detail. What is going on here is rather commonplace in all areas of retail business. I don't buy that much Audio online but fortunately the companies I deal with for audio have never given me any grief regarding a sale item.

That is not to say that there aren't dealers that use so called "sale items" as a come on to attract business. It's that simple

Early on in the audio game, I began inserting "No lowball offers, please" in my F.S. listings. I did so because I was often getting emails/posts offering 1/4 to 1/2 of my the asking price, usually w/no other questions about the item. That’s not a negotiation; It’s a drive-by opportunist hoping to find a desperate seller.

The other reason I put that phrase in my F.S. listings is that I’m plugged into the hobby and have a very good idea what different types of gear are selling for. Before even deciding on a selling price, I research that gear category as a last-minute sanity check...maybe things have changed for those who sell X, and I need to know that. Either way, the price I choose is carefully chosen to be market neutral (not too high, not too low), and also to reflect the condition and use pattern of the F.S. item.

I don’t get every single price right. When something isn’t selling, I’ll either reprice it, or take it off the market. Either way, I never accept low balls. Life is too short.

And it goes without saying, so I’ll say it: I also don’t make lowball offers of others.

Less than 10% sounds about right @gnaudio. 

I have to say this has been an interesting and useful thread. I made it all the way to the end so far, and that doesn’t happen very often.  So many good comments.  

I’ve been an A-goner for a while now but rarely buy much, other than accessories.  I’ve resisted the temptation to sell my old gear here partly because of the rude way people talk to one another; it sets a certain tone that makes me wonder if getting rid of something could possibly be worth the potential aggravation.  Audiophiles are such a sensitive bunch ; ).  

Communication IS key.  
If an offer is ignored that speaks for itself and I think it’s unnecessary to reply in a negative way.  However, a polite response that you are looking for something closer to asking price, continues the dialogue rather than ending it.  

I gotta say though that things are definitely different now than they were some time back.  I searched a few topics recently like subwoofer settings I think and was instantly struck by the difference in tone.  The older the thread, the more pleasant the conversation.  After reading quite a few threads from 10 - 15 years ago I realized I was not imagining it.  

My point is that while someone’s lowball offer may seem rude, there likely was no bad intent, and there’s nothing to be gained with a snarky response.  More importantly, doing your part to keep the conversation agreeable, benefits all of us.  

Now that that’s out of the way, does anybody need a 20 year old 7.1 ch AVR that weighs 65 lbs and has no HDMI switching? 
Lowball offers accepted.  
 

Woof 

I respond to low ball offers by informing the buyer I only had one at his offer and he just missed is offer being accepted 10 minutes ago. Sorry. But I have another one  at a little higher price if he wishes. It has worked.   This fun thread reminds me of the question, what is the worst thing in the world?  answer,   when 2 poor people owe each other, one can't pay and the other can't wait.