Ha!!
I doubt he could be successfully sued for fraud because he did not promise a product or service. As others have said, the money was used to buy billboards and advertising. As long as that advertising was delivered as promised, then there is no fraud involved.
People can buy billboards to advertise whatever stupid thing they want. If they use up all their own money in doing so, shame on them, but unless they can prove duress somehow, I doubt they would have a case against this guy.
