Can you actually provide a plausible example of where a JH-11/XX can conduct a hit and run attack better than a land-based truck with stand off missiles?
Those that show a preference for more complex attack vectors, pathing, profiles, and coordination;
Those that cannot be predetermined until after the start of the mission(target, waypoints);
Those that can be potentially called back(for military or political reasons);
Those where you need to rapidly augment, concentrate or maneuver your launcher force;
Those which involve other types of munitions, those not necessarily present on LACM warhead list;
Those that complex more than just primary PGM launch (i.e. air defense suppression, decoy launch, and so on);
Those where decision on how(and if) to proceed with the attack shall be taken on spot.
Trucks are cheap, simple, and easy to hide, store, and reload. These are serious advantages, but this is it.
In addition, bomber has a serious synergy with LACM(ASM) options dispersed throughout the region, i.e. it isn't just one option against another one. The same can be said about coordinating with ships and carrier-based aviation.