You think JK Rowling wrote every book herself? Someone printed the books shipped them, and sold them in stores. Workers whose labor created that billion dollar empire and were not paid equal value for their wages. Oprah's billions come from a media empire built producers, camera operators, writers, editors, all making a fraction while she owns the profit. Nobody EARNS a billion dollars alone. It requires extracting value from hundreds or thousands of people.
Did JK exploit them? Are they living off of food stamps and medicare like Wal-Mart workers are, specifically because Wal-Mart under pays them?
What about CostCo? Good wages and good benefits. That guy is (James Sinegal) is a billionaire too.
With Oprah. Is her brand built on exploitation? Are people literally suffering to put her in a Beverly Hills Mansion?
Are these people not being paid fair wages?
What if these women were "only" worth 100M? 10M? 1M?...
This is the problem with the "there should be no billionaires" analysis.
There's a difference between Hailey Bieber putting together a make up line and selling it for a billi, versus Exxon Mobile, Nestle, or Dole.
Your camp has to get serious about how to present a good argument, because "no billionaires" is not it.