I love a deal as I said, but typically the price is the price. I don't haggle at Asda checkout, at the jewellers or on amazon. I know what I have to spend before the off set.
I don't think its a statement of pride to discuss discounts. Its a personal thing should you wish to haggle.
I would imagine the last thing someone wants is a benchmark. In your case it may have been very quick, both times. But now people with a low budget will assume they can play the game and have people bid. The reality is that most people will just say, yeah, buy from Preston, were not running a charity.