I've added Yang's book to my reading list, as your review implies he's published things I've been ranting about for years over here in post-Great Britain. And for a presidential hopeful who isn't Bernie Sanders, this is encouraging stuff!
It wouldn't surprise me if McDingleberries does adjust prices based on time-of-day, demand, stock, etc. and as you say - a small enough amount isn't noticed by most people.
UBI = pension = unemployment benefit = income support = all those things that we need to survive in a world run by the greedy and deranged. The incredible success of the right in labelling the needy as 'entitled' while they take what they believe they deserve is astonishing. It used to be said that 'the devil has all the best tunes' but now we know he has the best memes.
Bring on the revolution - the people of France are our inspiration!