Most miners sell their bitcoins to buy more hardware and pay their electricity bills...
Why go through the trouble of running a mining rig instead of just buying the coins sold by miners in the market?
It is true that the majority of Bitcoins are held by a few early adopters (NB: not today's miners!). They will diversify out as time goes on. Wealth can come from skill, hard work, luck, politicking, etc... Rejecting Bitcoin because it enriches a few people in a manner that you find objectionable is... myopic.
Look around you, almost everything you do enriches one capitalist or another. Many intelligent people have tried finding a way around that, with limited to no success. Good luck.