Earlier quoted context omitted.
Even if they did take equity, I'm not sure that would be a problem. Charities and non-profits can make investments. For example, foundations have huge market investments. The distinction is that the owners can never cash out and put the money in their pocket. At most, they can take a salary with justification.
If you can't cash out of equity it makes a deeply insecure situation for everyone involved. It basically becomes a weird way to perform stock buy backs and would almost certainly be immediately exploited
I don't understand why a company would want to use a non-profit to buy back stock. The point of a buyback is to destroy the stock, driving up the price. If a non-profit holds the stock, then it doesnt work.