Only if the marginal cost of getting there is outpaced by the marginal return. If that wasn't the case, no volume-but-cheaper business could work. When you can have a ton of poor people, they are an exploitable resource for people who aren't selling iPhones (and if you pay attention to the description of eviction as a social problem maybe you'll catch a little more of the "exploitable resource" part). And it's nothing surprising--the historical examples abound of captive, poor populations who are used as revenue generators with no real recourse of their own. I get nothing out of the article that's "trading entirely on the ickiness" of selling goods and services to poor people. But I do get a lot of "poor people have basically no options because of systematic economic incentives to keep them there."