I find it a lot easier to hit "Sync" than to look at my podcasts and think "I listened to that one, this one and that one, so I can delete them, and hey! there's a new one, so I should transfer it..."
Nothing bgruber said contradicts that. But instead of a magic "Sync" button that only works in one program on one type of file, the "sync" operation on files can be used over and over again. I only "sync" too, because it's way faster than literally copying things over... but I rsync. Granted, I'm a power user doing this on the command line, but absolutely nothing stops you from "Dropboxing" your music player. Potentially literally.
This requires setting up syncing, which seems complicated when I just want to copy some files.