An oxymoron if I ever saw one.
My friends and I are in and out of top ten as axis. We spam bunkers and mines to cover our flanks or resource points. It is pretty common to see ten bunkers in our games at one time. Mortars, snipers, walking stukas, pwerfers, lefh and brumbars protect our bunkers from at guns. If one gets destroyed they are cheap to rebuild. Bunker spam is common knowledge for top players. If you are floating resources you would be retarded not to build one.