The reality is, which is conveniently ignored by many here and loathed by socialists, is that the the system is better than equal and the higher earners contribute the most and sustain those at the lower spectrum.
I am yet to meet anyone who propagates this specific type of misleading inequality information such as the content of the original article, that isn't simply envious of success, intelligence and wealth. Those who have genuine concern for low income groups, look at all the facts and figures, accept these, then work for change.
As it stands, life choices represent the biggest hurdle to the low income groups. Smoking, excess alcohol, unmanageable/unsustainable numbers of kids, buying luxuries (cars, sky tv, latest smart phone, big screen TVs, fashion items) which they could easily do without.
This study is also hugely skewed by the impact family size has on tax expenditure, benefits and burden to state funded facilities including services and housing.