I don't really care about fast food. That's strictly an optional luxury. If the experience sucks too badly, skip it. Grocery would be another matter.

I also think this hypothetical "scan to see your price" scenario is a lot worse. As things stand now, there's still a baseline price. If the shelf says $8.99 then you know that you may be able to get a better price through their loyalty program or with a coupon, but it will never be more than $8.99. In a fully dynamic pricing world where you have to scan scan to get a number at all, which is what a lot of businesses would really love to have, you'd lose that baseline. That item might ring up at $20 if the system decides I'm desperate or inattentive or just don't care. This is already possible online, of course. If it spreads to grocery stores, though, I'm going to start channelling Ned Ludd and it won't be pretty.