Yep, GP loses at bad-research bingo. Also, he missed the actual problem with this research: the subjects are divided into classes by self-reporting. So the headline should read, "People who consider themselves above other people pay less attention to others." It's not an un-interesting result, but it is not quite as interesting when you put it that way.
I've worked with people of all classes, and anecdotally at least I've found that F. Scott Fitzgerald was right: the rich aren't like you and me; they have more money. Old money at least lives a little bit like the people you read about in Jane Austen books; a lot of their energy goes into socializing with others of their class. So it would be interesting to look at old money/new money this way. Another interesting confounding factor is urban/rural. Rural people tend to be poorer. Urban people actually get more human interaction per time while participating in less per person encountered.
In most interesting social science research it's not the first and obvious way of dividing up people that draws your attention (e.g. rich/poor, young/old, male/female); it's the second cut. That's because most of our pop-psych deals in the first cuts (men are from Mars, women from Venus); the second cut tells us the ways our intuitions are limited.