Correct me if I'm wrong, but don't you need a "thing" to listen to cloud-based music too?
No.
I don't need the thing that is in my pocket, in order to listen to cloud music.
The thing that is in my pocket is a complete commodity in that regard. If my music player is lost, stolen, or damaged, I can immediately use any computer to listen to my cloud music. Including my netbook, my work workstation, my home workstation, or, really, any random web-cafe computer. Or I can borrow my friend's similar device, authenticate on it, and start listening to my cloud music on theirs ... until they need it back, in which case I log out and give it back. Then they pick up right where they left off.
And when I replace that player in my pocket, it will immediately have access to my cloud music ... without syncing. All I have to do is authenticate on it.
Your non-cloud music player doesn't have those advantages. Until you replace your music player, you're not going to be able to use any/every random computer for which you have access to play that music. It's going to only be the machine you store that music upon. At most, you may have it mirrored to a few other isolated computers ... but, again, not "any/every random computer". And, when you get your replacement player, you wont be able to immediately, in the store, start using it. You'll have to wait until you get home.
And, as I said earlier, if you're on a vacation ... that might be a while. In the mean time, I'll be listening to my music while you're waiting.