The quote was really ironic coming from him, because his entire career Booker has been at best an average player and has actually hurt his team with some "hustle" plays where he goes for offensive rebounds or steals in the back court. Sometimes he makes a big play, but the next time he's out of position, and that's why he usually rates out about as well as Jeremy Evans in terms of value on the court.
But I do like having guys on the bench who play hard every game. You need that attitude to permeate the whole roster and you don't always get it from guys who aren't getting all of the attention or shot attempts.