Crackheads trying to get their next fix just take any sort of electronics and get $10-20 for it. It doesn't generally matter what it is - they'll take it if they can get their hands on it & want to unload it ASAP. If they've been strung out & off the grid long enough, they might not know the difference between a walkman and a iPhone.

A professional thief, OTOH, probably does know what's worth taking and what's worth keeping. The problem is that, while committing a robbery, you don't exactly have the time or resources to go on eBay and price check everything you see. It's more practical to take everything that might be valuable & then figure out what's worth trying to sell after the fact.