They are obviously looking for money-is-no-object people who don't know the value of these items. I've also noticed a lot of winning bids on ebay that exceed KEH prices; obviously you take a chance on the condition from an ebay sale but you know the condition from KEH, and there's little or no return or warranty period compared to KEH. I guess some people get caught up in the bidding frenzy.
I have a Konica Auto S2 that I bought from Greg Weber two years ago for $200, refurbished to mint condition, including the meter battery voltage modification. If you really want to use that camera, it is well worth it compared to messing around with $50 versions that have sat for decades and won't work properly; even if you can return a few of them, you'll be out shipping and can be out of $100 with nothing to show for it. And it was certainly much less than $2,125 from this place.