So, more broadly, you might be asking me “why waste your time selling $100s of furniture?” which is a completely fair question. The opportunity cost of the time spent selling it was far greater than the benefit I got. From a pure optimization perspective it was a bad use of my time.

But also I just moved to the other side of the world and had an apartment filled with furniture that I needed to get rid of. And I am the type of person who doesn’t like waste, so sending everything to the landfill was misaligned with my personal values. And also I don’t work 24 hours per day, so it’s not like this effort takes tome away from working on the meaningful deals.

It would be reasonable to ask “why not give it away for free?” In my experience, customers that pay you nothing are a much bigger burden than customers that pay you something (and, in fact, I find that higher revenue customers are much easier to deal with on an absolute basis).

And then your more direct question: why negotiate at all? Why not just accept the offer and move on with your life? I think your guess is correct: I am a negotiator at heart. I really truly love the hustle, in all aspects of life. It doesn’t matter whether I’m earning $10, $1000 or $100k: I love making deals. And this part of my character is probably a big part of why I’ve been successful in business.

To your final point - the marginal benefit of negotiating vs. being perceived as petty. In all of these situations the audience is different and their lifetime value is different. It would be foolish to negotiate with a $100k customer over $100s; you’re right to assume that the customer might perceive it as petty (and such a move would probably diminish their lifetime value). But, on the other hand, if you sold something to a random person off Craigslist where their expected lifetime value was in the $100s wouldn’t it be foolish to not try to maximize your outcome, especially if it only added a minute or two to the transaction?