What happened to surcharges/exchanges? Repurposing old parts

Back when I first worked on cars, nearly every non-consumable part I bought was on a surcharge basis, i.e. you'd get your shiny new part and hand over the worn out caliper, suspension arm or whatever else it was you were replacing for a small discount.

Now, with the exception of bigger items like steering racks, noone seems interested in taking the old ones.

I've amassed a small collection of parts that "will come in handy" next time I need to replace them (Volvo lower arms, fuel pump, a multitude of calipers, dual mass flywheel) but in reality the ones they were swapped out for will outlive the car.

In some cases, for want of only a press in bush these will now end up in a scrap pile somewhere, which is a shame as they are perfectly serviceable and I imagine the expensive part of manufacturing them are the non-wearing bits. Ironic given the ever growing push to go green.

So my question is... Does anyone still do surcharge returns or are they a thing of the past? Is there anywhere I can give the old parts away for firms who DO still recon base parts?

As above, refurbed brake calipers from the likes of Pagid are definitely a big thing (I have 3 of them on my car currently).

If you watch any of the Youtube channels on people rebuilding write-offs there seems to be several firms rebuilding/reloading airbags, seat belts, etc. rather than having to buy new ones.

Turbos seem to often be sold on an exchange basis and rebuilt.

As for most other things, modern manufacturing in the far east is probably so cheap that there isn't the business case to either refresh things in Europe or ship them back to somewhere cheaper to be done up.

And of course, electronic items that can't be bought new can be fixed up.