Why?

Geoffrey Canada (quoted in Ticket to Teach from DfER):

“We say to these young people, ‘We’re going to make a deal with you. We are not going to pay you a lot of money, but we are going to give you a lot of time off.’ It’s a terrible message we’re sending.”

Aside from the fact that these days it ends up being less free time than you'd think, exactly why is that a terrible message? Is there something morally wrong with preferring free time to more money?