I think personally that if the person has an outrageous number for what they want, I will reply that it's not a realistic price. The sarcasm is only reserved for the fine folk as yourself.
I don't think it hurts people that post here, eBay is the true market, as much as everyone hates it eBay shows what the current "I'll pay this much for it" price truly is. Most of the folks that post here know that, with the few exceptions of those that have gone to a boutique vintage drum website and got their heads filled with illusions of grandeur.
I had someone send me a email regarding a Slingerland bass drum shell that I have for sale. The box it was figured for to be shipped in made the shipping to the East Coast close to $80.00. The emailer was kind of sarcastic, and I told him exactly why it was like that. Then I did some more checking and found that I can ship it for cheaper, if I pack it real tightly in a smaller box. I'm not too keen on not having a larger box (less cushion), but if that's what it takes to make potential buyers bid and buy, I do it.