I do not oppose "capitalism" per se. For one thing, this is way too abstract for me. I oppose specific business practices, policies, and people. If it does not have a name and an address, "opposing" it is probably a wild goose chase.
On the balance, however, I am for big corporations (planning) rather than mom-and-pop shops and free market chaos, for big cities rather than small podunk towns (and their insular mentalities), government planning, balance of power, due process and protection of unpopular minority rights rather than populist mobilization. I am with John Kenneth Galbraith who viewed big corporations more favorably than small market players, and, for that matter, Karl Marx who saw "capitalism" (i.e. industrialization and institutions it created) as a great universalizing force overcoming the vestiges of feudalism, backwardness and the idiocy of the rural and small town life. Like Marx, I do not want to destroy capitalism and replace it with a populist podunk utopia of one sort or another - I just want that its benefits are extended to as many people as possible, rather than to a narrow elite.
So I have no problems with my retirement portfolio being invested in stocks at all - in fact I elected only a small share going to "socially responsible" fund and primarily as a hedge against my other allocations.
Wojtek