If you're born a millionaire like Paris Hilton, and you capriciously decide to become a large shareholder of Walmart's stocks one day, you... well, you just sit back and watch the money roll in without doing anything. Even though you're providing zero value to society you make a very large amount of money. In this way, not only is clarky07's profoundly and bizarrely misinformed, it is also selfish and offensive.
I'll be the last to argue that we live in a meritocracy but in your example the capricious heir is in fact providing capital to the economy, taking on the risk that if that business fails the capital is gone.
Investors wouldn't take risks if they couldn't reap rewards from them, which means workers wouldn't have the jobs either. The end result would be even less fair.
In any case, the modal investor isn't Paris Hilton or Warren Buffet, it's an ordinary working stiff trying to save for retirement in his 401k, or a pension fund for workers at other companies.
Someone who's working at Walmart does not make a lot of money, they most likely cannot afford to give their children the best education, they cannot afford a reliable car, they're more at risk of failing to make the rent payment due to some unforeseen accident.
Someone who's in the financial position to be able to comfortably invest their money, or is otherwise a millionaire, even if they lose a good few hundred thousand dollars, it will not affect them much. At least, not as much to pose the question of if they'll be sleeping on their own comfy bed or in a homeless shelter.
When you say that people "deserve" minimum wage because that's all of the value they're providing to society, this is what you're talking about. You're talking about putting them in a very shakey position, you're talking about making them borderline-homeless.
And we're not just talking about millionaires bearing the risk, either. About half of Americans own stock one way or another.