McDonald’s prices are cutting out customers who make less than $45,000 a year, which is about one-third of Americans. It hasn’t hurt the Golden Arches – by any measure, business is booming. But it’s a stark reminder that a growing number of people in the US are struggling to afford the basics. Bloomberg Opinion’s Nir Kaissar breaks down the data to explain why it’s time to add burgers to the list of what separates the haves and have-nots.