How is any of that different to just paying out the money to shareholders, who can individually choose to champion said causes themselves? I don't see why the company should do so.
I suspect the biggest difference in how I see this compared to the feeling I get from you is that most things are positive-sum games in capitalism. One man's profits is another company's capital is another employee's wages. The profits of the company don't disappear, locked up in a bank never to be seen again. They get invested by the shareholder somewhere else, or spent on something, and so on. There's nothing inherently "greedy or evil" in this process.
This process can be very indirect (how does an investment in Apple today help? By providing the incentive for many of these companies to be built and made public in the first place, sharing their profits across many people), but it is there. Some explicit redistribution may be necessary, as in many countries with public healthcare or strong welfare systems, but having a stable core of a private market helps generate the overall resources to run everything.
Maybe there's a better system that can distribute the wealth more evenly - but the best examples we've seen thus far come from welfare-state western democracies, which all grew up on the same basis (and are all poorer on an average basis than America, who has a much weaker welfare base). These aren't necessarily related of course, America is stupendously rich in a lot of other ways, but it's food for thought.