Runway cratering in WB sucked, which is why HT didn't put it in AH. As hub said, it was WAY too easy to pork fields that way. You'd spawn at a field, thinking all was fine, no vulchers around even, and snap your wheels before you even got the tail up. Now imagine in AH where porkdweebs are much more common, especially in buff formations, and you have a total mess for gameplay. Whoever got in the air first would shut down most fields of the nme and dominate from then on. Either that, or all sides would go on a cratering binge and there'd be no useable fields within 3 sectors of the front anywhere on the map.
It's already a big enough problem with kamikaze jabo porkdweebs taking out the supplies and ord at fields all over the map. If they could totally shut down fields....