" ...I don't see the point of trying to "escape" the browser chrome, or trying to copy the look and feel of native apps. If web apps are going to be cross-platform then they should embrace not being truly integrated with any native platform."
I kinda feel you on that one - and to be honest, I'm not sure how you would "turn that off" but if memory serves I think it only happens if you opt to "add to home screen" which Chrome only prompts for things you visit a lot.