Regardless of where the money comes from, it is money that someone else cannot have. In the case of government funds paying a welfare recipient, that money comes from taxes. In the case of a company that used my investment, that money comes from the corporate profits that they would have kept, except for the fact that I have it now. Now you might argue that the corporate profits were given up voluntarily while the taxes were paid involuntarily. But the corporate profits were given up only because there would have been very negative consequences if the company had failed to live up to their contract to pay the investors their interest. If that company could have gotten away with not paying investors and have no negative consequences, you can be sure that’s what they would have done. This is comparable to people paying taxes because there are very negative consequences of not paying it. So the distinction between voluntary and involuntary contributes is not that great.