Only because of the DJ
And there was simply nothing there that could replace it.
Now there is. An for the majority of DJ`s, who don`t want the finer points of vibration effects etc for scratching, there is now something thats probably easier to use.

I think as a point made earlier by someone, being only a single format release, restricts your audience mainly to DJ`s. And there aren`t that many DJ`s. So there are a lot of people left out.
I think dual format releases would be wise.
however there needs to be good promotion and infrastructure to support this new market.
And the current distributers are having a hard enough time just selling vinyl.
So there is no easy solution.