It's still music on those tapes, and people still want to listen to music! People love physical formats too as vinyl shows and cassettes have unique pull out covers and stuff. As with ANY format, some will be uniquely released on cassette, different versions, different B-sides etc etc. People collect music first and formost.
I can't understand any act of throwing away whole collections of a particular format unless the music taste is utterly shit.
You don't actually say they were 500 pre-recorded cassettes though - if it was 500 mix tapes or stuff off the radio then no bother.
If it was 500 pre-recorded then WHY??? Give them away on an music loving, hifi loving forum at least.. Don't understand the throwing away of music.
Some people happily spend £5 on an interesting cassette on eBay
- it's a physical format with unique pull-out covers too, some with album art or band photos etc not on any other format.
There are many cassette audiophiles too with a whole display of Nak Dragons, ZX1000s, Tandberg 914s etc etc and they need something to actually play on them. If they've the money to spend on the machines, they've the money to spend on the pre-recorded cassettes too. I guess some also just like to record, hence the prices of fancy metal cassettes.