I only started playing poker around 2-3 months ago and prior to that I'd never seen anything other than Texas Hold'em and only ever heard of other forms of poker. If you'd have mentioned Omaha, Stud, Badugi, etc... to me then I wouldn't have had the slightest clue what you were on about. I think it's likely the same for most/all other non-poker players. They're not going to come into poker by anything other than Hold'em.
I have this month's poker schedule for the Grosvenor here in front of me - cash games are Hold'em every night and every night it's Hold'em tournaments (aside from one night where it's Kalooki, which I think may just be running due to the ethnic groups in this area, though maybe not?).
Ultimately, my opinion is - nobody other than poker players know any games exist other than Hold'em, as such, nobody other than poker players are going to play such games.
(As always - Excuse my drunkenness, please correct anything I've said that is wrong)