This culture developed for websites and HTML for a while (and resulted in some ugly websites!), but this has been subsumed into other tools now so most(?) website-creators have little or not clue about the underlying tech anymore.
I guess a big part of the success of HTML in this area was that the code was already there in front of you, and ultimately HTML document-writing has a lower barrier of entry than programming.
There is always a significant barrier of entry to programming and fixing your apps. You need to learn the language and the codebase. I don't think we can expect much from mass programming beyond changes to simple apps written in easy-to-read/change languages, as most people really aren't interested enough to invest more effort than that.
Easy app-development is definately key. Arduino and Android have both had wide success at least partly due to programming being made relatively straighforward.