Well, Android Apps run on Dalvik/ART, which is not HTML5/js but I agree, it's not a real difference, except in FirefoxOS marketing strategy, targetting ultra low end devices with heavy (heavier than ART) apps will result in an absurdly unusable system.
Well what I was trying to say is, Firefox OS apps are just web pages. Saying that an Android user is locked into the Play store unlike a Firefox OS user seems silly, because you don't need a single Android app installed to mimic the functionality of Firefox OS. All you need is the browser.
