Gratton also allegedly believed that, in a previous existence, he was an executioner who had stoned people to death, and thus was "fated" to be a goalie as punishment. While with the Toros, he refused to play because the moon was in the wrong part of the sky, thereby not lined up with Jupiter. He later stated he did so to protest against the firing of coach Billy Harris.
Throughout his career, Gratton, nicknamed "Gratoony the Loony", was known for his eccentric personality and outspoken character, often drawing attention away from his talent. While playing in the WHA, he once hurled insults against the opposing team's fans in San Diego ahead of a playoff game. Legend has it that Gratton once told his teammates he was reincarnated and had once been a soldier in the Spanish Inquisition.