Without need to look the studies and statistics, I think everyone know if the wealth gap between the poor and middle class with upper class are extremely far.
True, rich getting richer and poor getting poorer, so that definitely makes the gap getting bigger as time pass by.
The poor and middle class aren't trying hard to become rich, because their mind are mostly want to earn a lot money via instant which actually impossible! majority of the people this group are spent their money to buy branded stuffs in order to get respected by many peoples. Do you know which one is selling the branded stuffs? it's the upper class!
The poor and middle class are trying to be rich but they are given limited opportunities. With less money in hand, they are unable to compete against tycoons which can spend millions and be able to lose millions trying to experiment with certain trends and businesses. It isn't about people in middle class spending their money to buy branded items, if you look at these people, most of them are contented to have knock off items, or imitations to use since they really lack money to buy those branded ones. It is the availability of funds, influence, and of course connections that set the difference.
The upper class already have a lot business, they're also make a lot money from stupid poor and middle class, so it make them can expand their business become bigger and bigger.
Saying stupid is a very harsh word. People doesn't want to be poor or in a middle class, if they have a choice, they would choose to be born in a wealthy family, it is that they were born in that class, and who know how hard they are trying to get out of that situation. Not because one of 10 people are branded crazy, you can generalize all these people are doing the same thing.