Ministry, Nine Inch Nails, Rob Zombie...
Instant credibility and buzz word re-definition when you associate it with names of this caliber of draw. Toss MTV a promo video or ad spot with the term "industrial" in it, and it is instantly part of the pop music lexicon. Or run an ad with Rolling Stone or get a single review with that word in use. And when you're trying to appeal to a "harder" crowd, mostly metalEds, industrial is a smart way to go. Has that blue collar, rough and manly implication automatically associated with it. Instant interest. This was also around the time when goths and art types were befriending Metallica, The Cult (Rick Rubin years), etc. Historically, a few things fell into place for the term to be bastardized, redefined, and used as a sharp marketing weapon.
I can remember opening up Industrial Nation, and it looking very much like a metal magazine. Not limited to the music, but fashion and aesthetics had also crossed paths with the electro-hybrid metal music. It looked industrial. Only makes sense because it was never about the sounds anyway.
EDIT: was thinking about this and the power of MTV at that time. John Norris was somehow involved with 120 Minutes; host or writer or producer. I believe he also had something to do with Rolling Stone (maybe that was Kurt Loder). I'd bet a good chunk of money that if you combed through those first five years of 120 Minutes, someone mentioned Throbbing Gristle or Psychic TV. My point is that I wouldn't be surprised if the redefinition of industrial was spread somewhere on MTV. The idea likely came out of a marketing boardroom, but MTV must've been a key player in exposure to it. It would be so much easier to take an already used term and redefine it. It has a built-in credibility from the underground fringe types, and is attractive in the ways I already mentioned.