Define work. Violence is the worst solution to every problem, but it always WORKS (badly).
The main reason why rich keep getting richer is because people avoid responsiblities, instead letting other people tell them what to do, to think for them, and to decide for them. As long as this continues, I dont think any system really works for long. People want freedom, that is to say ability to do anything they want without getting burned; but in reality, action has consequence and even if no MAN oppress you, the actions you take sometimes backfire. But if the decision was made by someone else, it's not really your fault, yeah?
Whatever, but you're the one to suffer for it, so who cares who did it, could you have prevented it?
As such capitalism (by which I suppose I mean Free Market Society) does work, if people would learn from people that are better than them. Hence someone might get rich, but others would eventually surpass him. The problem occur when the rich try to manipulate people into stupid or followers or try to prevent information from going around.
Or when people, instead of thinking things themselves, just wait for someone to think for them, then grab the knowledge and instead focus on winning. This leaves the guys who did the research poor and bitter, and soon research stops, since there is no profit in it. Or, more likely, research continues, but the smart people instead hide what they know and use it for their own good. And become the leaders, who oppress people into stupidity and slavery.
Having said that, I'll say that political equality cannot exist without economical equality.
But since the real problem is rather the people, not the system, alternative solutions don't really work, such as oligarchy-communism, where the few grab everything and then try to rule people into being great and good; Since, by doing so, they declare themselves leaders and promise to handle the thinking themselves (and the people, hence stop thinking, accepting their role). Such a system would never evolve into economical equality, since the leaders would never come out of office.
So does capitalism work? No. But I guess people need to learn it for themselves. The Hard Way.