I'm not going to argue about relative or absolute poverty here. What I am going to say is that it is inequality that is the pernicious evil in society. People may not actually *be* poor, according to some arbitrary chart, but if they see that those at the top of the ladder are vastly wealthier than they are, and that those people are getting more and more of the pie each day, as inequality grows, then those people *feel* poor, and angry to boot.
I'm talking here about the behaviour of CEOs, bankers, the city "wealth creators" who are seemingly only creating wealth for themselves these days, shipping their profits offshore, avoiding tax and therefore placing a larger burden on everyone else. Philip Green and his Monaco-resident wife are splendid examples.
Societies that are more equal are entirely happier and more pleasant places to live. A multitude of studies demonstrate this. Growing social inequality tends to result in civil unpleasantness.