The idea is; Bitcoin won't always have expensive fees to pay for small transactions. Technology like Lightening, and Segwit try to tackle this problem, and there will likely be more, and more improvements in the future. Currently, I would probably agree that Bitcoin isn't suited for micro transactions, such as every day transactions, however that doesn't mean it'll always be the case. I also imagine that restaurants won't require block confirmations, because the likelihood of a double spend is relatively low, and there's probably just as much risk as someone paying with a fake bill (sometimes even without knowing themselves).