The capital in capitalism comes from the labor of the working class. Not content with exploiting us at work, the capitalists take a second hit at us by selling us back the products of our labors. As consumers we have to pay directly or indirectly for everything we need to live. In capitalism there are many divisions fostered in the work force used to keep the working class divided. Racism, sexism and homophobia are the most profitable divisions from the capitalist's point of view.
Capitalists compete with each other to make profit.
The working classes have to compete against each other to survive in the market for labor. This has the effect of tending to put us in a defensive position. To increase the amount and rate of profit if at all possible. These are the driving forces behind capitalism. This is the grim reality of capitalism as a way of organizing society.