Do you really think that's more likely than the defendant just stealing some music?
Actually someone coming up and getting on your wifi and downloading music is much more likely than you breaking into a major label's office and making a copy of the source files for the song, deleting them behind you.
Or perhaps you meant to say "More likely than the defendant just committing copyright infringement" Theft has a definition, it is not synonymous with copyright infringement.
"It is better for civilization to be going down the drain than to be coming up it." -- Henry Allen