If your equipment are not Apple, they will still pick it up for free via Sims Recycling Solutions. [2]
[1] - https://www.apple.com/recycling/ [2] - http://oem.srsapp.com/applepoweredbysims/
Technically nothing on that page days they don't just throw all the returned iPods into a lake. Well of course they don't, but neither do we know what they actually do.
Actually, if you click through on the GPs link Apple provides information in two links with further links to PDFs and FAQs.
Trade-in would imply that you are also purchasing from Apple as well. I didn't read anything condition requiring any purchases to take part in Apple's recycling program.