Cartridges: Complete Scam?

Whoever disagree with (market) prices assumes some other
''concept '' or theory of value. Say , one assume some ''real value'' different from the (market) prices. As I try to explain with classical economist who distinguished between 'value in use'' and ''value in
exchange '' ( aka  prices) . Alas they deed not succeed to formulate any  consistent theory of  the ''real value''. Except perhaps Ricardo in his  ''corn economy'' in which all ''values'' are expressed in terms of  corn amounts. So one should be aware what one assume.  There is no other economic theory than theory of (market) prices,

So I'm browsing through the cartridge listings. It looks like the ads fall into one of two categories:

1. Dealers trying to move cartridges at full price while pretending they are massively discounted.

2. People trying to unload their old junk.

I've learned already through buying vinyl through eBay and Discogs that people habitually lie about the quality of their items -- every single "as-new", "pristine", "looks unplayed", etc, record so far has has been dirty and scuffed. Unless it's literally new in sealed factory shrink wrapping it'll end up being someone's beaten-up crap. 

Does the same mentality apply to selling cartridges? At least when a dealer is selling their lightly used cartridge for basically full price, it'll look and probably is in good shape. But some of those private ads the casings look beaten up -- why do I want your beaten up junk bro? At least sell it to move and don't lie about how wonderful it sounds!

Or is it everyone is scanning the listings non-stop for actual good deals and snap them up instantly so that all that's left are the dealers like that guy claiming to sell XYZs for 40-50% off (I do like the ones that have that cool little ball in the front...) and the old junk no one wants?

Where do you find rare cartridges that compete with the finest modern cartridges?

I don't think you do. Buying a used cart is worse than buying a used smartphone.

Yes there will be honest sellers who have took great care of their stuff. They are usually the ones who will point out the smallest of blemishes and have kept all of the paperwork. However, for every one of these there's at least a dozen who should have the phrase 'caveat emptor' emblazened over their ad and tattooed upon their foreheads.

the OP makes an amusing comparison between
Magico's and Elacs - funny thing is that Magicos really need both grunt and dexterity to really come alive - think Soulution and Constellation. You ain't gonna make em 'jump' nor would anybody pair magic's with a £400 mass market amp with significantly less power and grunt - although with the Elacs you most probably can and will. So your comparative sample merely supports the viewpoint that one does not pair a LOMC with a load of equipment that does not match the MC. bringing out the best in a top flight MC is going to be a far more expensive and fussy procedure than a £200 MM like a cheaper mass market speaker against a high end design

Without a list of your equipment there is no way to determine weather or not you could notice a difference at any level of cart. Ie: TT phono pre, arm, amp, speakers ect. Give us a base point to start.