Tire burn......
I once had a senior Boeing engineer sitting in the cockpit on a flight to Seattle from Copenhagen (before 9/11). He had a fantastic knowledge of aviation, and he had an answer to the question in this thread.
He said that the main reason for not having such a system installed is, that the rotational speed of the wheels MUST match the actual ground speed closely in order to get any significant decrease in tire burn. This close match is very difficult to achieve for several reasons, so combined with the other negative factors (weight, costs etc...) makes an "anti tire burn" system a non starter.