In my limited experience the 'elite' brands are some of the worst offenders. My most recent experience: I wrote to a cable manufacturer, asking him if I could pay him to shorten and reterminate a pair of expensive interconnects that I was thinking of buying on the secondhand market. His answer was, of course, 'no'. This is a tiny company that has no dealer representation in my state.
Hostility from manufacturers
I know its a cottage industry, and margins are thin, but I still think its shortsighted of them, and harms the industry in the long run. I'm talking about several interactions I've had with manufacturers after having purchased their products on the secondhand market. They should think about what would happen to their prices and their sales if their products were not resellable. Maybe they would like us to send our components to the scrap heap every few years or so just before we purchase their latest upgrade.
Fire away..
Fire away..