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

It may well be an issue of culture, or education. There are times a potential buyer, giddy with the thought of falling it the deal of a lifetime, is tiresome and unappealing when parting with something you have found value in. Perhaps like shaking the hand of a teenager who has just come out of the bathroom with a skin mag and would like to meet your daughter. She may be technically "fair game" but that does not mean it is pleasant to deal with the pimples or greasy hand. We are in this for the pleasure of music not low life ego trips.

@simao Seems to get it. First of all from a selling standpoint. If I want $2000 for an item, I'm going to list it for $2500 so I have some negotiating room. If someone really wants the item and they offer my selling price or even a couple hundred less, I still come out ahead. From a buyers stand point, you have to know what you are willing to pay for an item. I have received many offers at a low price and then neverget a counter offer. I think a lot of people don't understand the art of negotiation. It's a used piece of gear. You want to sell/buy it. You should expect to negotiate. Some people are so offended on either side of the trade. Don't be offended.....negotiate! If I am willing to pay the $3500.00 asking price for an item, my first offer is not going to be the ask. I will say something like, can you live with $3000.00? If I get a yes, then I know the person is wanting to move the item on, If I get a no then I will split that amount to see if we can settle at the $250.00 difference.

You also have to understand how to control a situation. When I purchased our home I told my wife, we're going to offer "X" and they are going to counter with "Y" and we are going to quibble over a few thousand dollars on a large dollar purchase. I told my wife that if we pay the asking price the conversation is over an we control the situation. We offered full price with possession at closing and made the deal. No one here should be offended. If you receive an offer simply justify your price....(this is a current model unit that is in excellent shape at half the price of new) If they aren't willing to come back with a better offer then so be it. There are always ways to negotiate, both parties need to be willing to do so. As a successful salesman I can tell you that you don't get unless you ask. Have a starting point but be willing to haggle. For sellers, understand that people are going to go fishing to see what they can catch. Simply counter offer and then you know where the person is really at. Remember, if you are "offended" then that is on you, not the other person. Being offended is just plain dumb. 

@boxcarman Don't you see your problem? It's right there in front of you. You expected $800.00 for an item and stereobuyers offered you $400.00. What did you expect? It's an $800 dollar item and they are a reseller. They're certainly not going to offer you market price for an item, You have to understand the situation. See the last sentence of my post above.

@travelinjack BINGO!!!

I feel the same way @bubba12.  What does it take to say no to a “lowball”? One second? Often if you thank people for their interest and politely decline the item now becomes something they can’t have and naturally they want it more.  Then they can’t let it go and negotiations start.  I’ve often made reasonable sales that started with a “lowball”.  Anybody who lists an item for sale and notes “lowballs will be ignored” is potentially missing lots of opportunities to sell.  Not very smart.