Why not more dealers take trade ins?

I think you will find dealers perfectly willing to take trade-ins. When you have something they know they can sell for a profit, they will. 

Something to consider,

I had a shop and repaired equipment. If the equipment was used, or taken in as a trade, the SELLER had some obligations, in brick and mortar stores.
I had to be listed as a Pawnbroker on my business license.  Where I did business, was subject to some pretty intrusive BS, if the local PD wanted to.
The word, "Refurbished" or "Used",  gave local PD a lot of power to pretty much do what they wanted.  Could pop in unannounced look the place over... I did't care, but I didn't like some of the rules.  In 20 years, 3 visits and  always a rookie..

Always a BOLO for some high dollar stereo, or computer gear.

Back then computers cost more than stereo gear, by a long shot..No inexpensive computers back in the 80s 90s.

Maybe that some of the reason for NO TRADE IN...

Regards
 

I think that almost any dealer will take a trade-in. The problem is the delta between what most buyers expect to receive for the trade-in gear vs. what a dealer can actually pay for that gear and cover additional direct expenses such as service and/or cosmetically restoration (if required), insurance, advertising and still make a reasonable profit.

My experience as a dealer was that most (but not all) guys expect a dealer to credit them for their gear at "retail"; that is the same as they see units advertised on Audiogon and other sites. Then they want a healthy discount on new gear, typically 10% of which is returned due to audiophile buyer's remorse, plus onsite setup and free support for all audio gear (purchased from the dealer or not) for life.

Sorry, what was the OP asking about? Oh yeah, trade-ins. I think that almost any audio dealer...

Adcom takes trade ins. I won’t buy adcom these days, as they are not the same company from them80’s.
 Even them80’s, amps were so bright,it hurt my ears.

 I listened to those 80’s 565’s or 575. MOnos through house klipsch horns, at 103-104db @ 1W/1/M
 it was painful.

Ebay and Audiogon.

Honestly.  They are competing with them, and they'd rather you just go ahead and do the work yourself.  Not to mention covid is really slowing down everything, why should they double their stock of used goods??

I mean, of course this will be dealer/item dependent.