There is most likely a safety angle to this. If you don't keep it in check people could get hurt. Last year running Jr stock at Atco, I had some water get under my rear tires and about the 330' mark my car made a quick right turn and got on 2 wheels. No body was hurt and nothing was damaged, ( Except my shorts
) but water came out of my cool can because ice kept a part of the lid from sealing. The same thing could happen from a bag of ice, or water. I bet that never happens again to that guy that got dq'ed. Just my 2 cents..