I actually don't have a problem with this as, if they let it happen, when teams think a change of coach is in order, they can then start shopping for coaches with jobs from other teams while offering players in return for letting the coach out of their contract.
I think that's bad practice. The coaching profession in the NBA, as a whole is already so unstable(witness Karl, Doc, Hollins and VDN all taking their teams to the playoffs but leaving their teams), why add to that instability?