Bale's agent Barnett appeared to point the finger of blame at Jose Mourinho when asked why his client is not featuring more prominently for Tottenham.
The 31-year-old Welsh star made a high-profile return to Spurs on a season-long loan from Real Madrid over the summer.
But he has struggled to break into Mourinho's side, and has made just two starts in the Premier League all season.
Speaking at a Business of Football summit, Barnett gave a cagey answer to a question about Bale's lack of action.
"He's towards the end of his career. You'll have to ask Mourinho that," he said.
"When they say what's happened to him, he's won more trophies abroad than any player in British history. He's done very well financially, he has money for the rest of his life."