It's time for github to start offering some basic hosting infrastructure of small projects, a light heroku, at least for JavaScript (which kind of already works).
I'd pay extra for that, I (we all) have a bunch of personal sites, landing pages, marketing sites and tiny side projects that'd love to not have to deal with hosting – I think they'd make a killing, but also think must be in the works.
Also the mental jump. Just because something is easy for them to do doesn't mean it is worth the distraction cost.
Github builds tools for developers. Atom, chat (abandoned), Pages, Gists, and github.com all fit within this. They tie into how teams operate. Serving JS is tangentially related — certainly something a web developer does — but not really core to their mission.
I'm keen to the demand level via our research. IMHO it's not worth it for their business size and growth plans. Their other initiatives are far more lucrative. There's also a lot of competition at that level.
I think of this more as a convenience feature for their existing business that adds value. They use this instead of the "project page" design that the other code sites used, and it gives their users more control over the presentation. Which is awesome, and feeds into my conspiracy to get everybody to know and use HTML for presentation. :)
I'd pay extra for that, I (we all) have a bunch of personal sites, landing pages, marketing sites and tiny side projects that'd love to not have to deal with hosting – I think they'd make a killing, but also think must be in the works.