A lot of people are not as dumb as we give them credit for (granted, many can far exceed our expectations), but not all. They have bought and sold on Ebay before and have an idea of shipping costs, Ebay and PayPay fees, and the amount of time and effort involved in building a listing, packing and shipping, and the potential for "issues"--claims/refunds for no apparent/valid reason. I buy and sell on both Ebay and CL, and if I see the same/equivalent item both places, I expect the CL selling price to be 25-30% less than Ebay prices.
Granted, CL has its advantages in that you can physically go and evaluate the item in-person and BIN--really NOW--as in load it in the car and take it home now--not waiting for shipping. OTOH, you have to personally deal with a**holes, drive (sometimes hours) to be seriously disappointed, or end up in a neighborhood that you might get caught dead in. BUT--the seller is getting the full amount of the transaction price, so packing, shipping, and Ebay/PayPal fees should be removed from selling price equation. I'm not paying for services not provided--packing, shipping, PayPal and Ebay buyer protection and convenience of delivery.
I recently sold a fairly "high-end" R2R deck--listed on both CL and Ebay. I listed it for $500 more on Ebay than I did on CL--I had to, in order to end up with the same amount of cash-in-pocket at the end of the day. BTW--it ended up selling on Ebay at full asking price (BIN/OBO), before I got anything more than CL "lowballer" offers from CL--so you do sometimes "get what you pay for" in terms of Ebay/PayPal fees.
OK--rant over, and back to the OP.
People are also beginning to realize that some of the mid-range/less-desireable models in a given line-up are the real "sleepers"--they have a few less watts and a fewer "bells and whistles", but sound just as good (in some cases, better) than their bigger TOTL brethren, so values are increasing, relative to where they were, say 5 or 10 years ago.