I skimmed through a bit of the thread, and I thought I'd add my two cents.
There seems to be a whole lot of idealism going on here. I think there are some who need to step back and think about things realistically.
There are people who want to buy and sell things related to keyboards (or just other cool stuff). Sellers will want to make a reasonable return on the sale, and buyers will want to snag an item for the least amount they can. New things in high demand are going to cost more, ie clacks. This is supply and demand. Clacks have a low supply pretty much all around, and since for whatever reason people seem to freaking love them, their demand is high. Guess what happens to the price when you have low supply and high demand? Price goes up. Sure this isn't ideal, but it's reality.
Getting back to auctions, do they belong? Maybe. I personally think auctions are a perfectly fine way to sell something. It can benefit both the seller and buyer, for various reasons that have surely been outlined already. I feel the only issue is the quality and setup of an auction, which is completely a result of the seller. A good seller who sets up an auction with clearly defined rules and stays on top of the auction to handle it is fine by me. A bad seller who sets up abusable or just plain bad rules for the auction is going to have a bad time. Also, I think it should go without saying that if you don't like somebody's auction, don't bid. It's that simple. Along the same lines, somebody's auction thread is not the place to complain about the auction.
Having auctions on ebay is great, but I feel a primary reason that people want to hold auctions in threads here is visibility. With an ebay auction, no thread is bumped, and chances are people will only see your auction once or twice, unless they're actively bidding in it. Here, when a bid is made by way of a reply to a thread, it pops the visibility up to 11. But of course this causes problems like forcing down other threads in the classifieds. There is however an easy fix for this: Have an auctions subforum, separate from classifieds.
Good things can also be done with google forms, or maybe if some enterprising individual wants to set up a bidding service, we could see some really cool auctions. Classical auctions have issues, like sniping (yes it's an issue in my opinion), so having a bidding system that can be configured to do interesting things could lead to some good auctions happening. From my minecrafting days, I've seen a couple auction methods implemented on servers to buy in-game loot, each with its own positives and negatives. I've seen, for instance, an auction system where you place hidden bids, and if you bid higher, you become the bid leader and the second highest bid is announced, but if you bid lower, you are informed that you are not the highest bidder. However, the winner of the auction only pays an amount equal to the second highest bid. The idea is that you bid the most you are willing to pay, and then any bid lower than yours will raise the amount you would pay if you won.
TL;DR: Auctions are cool and useful, but should probably have their own sub-forum. Users should be able to leverage a variety of auctioning methods based on the auction they want to run. Ex: ebay, google forms silent auction, etc. If you don't like somebody's auction, you don't have to bid.