Obviously you haven't ever even owned a 4wd. Explain to me how it's not as efficient as an MFD? It has the same engine, the same number of differentials, and a transmission with two more gears. It is WAY more maneuverable than an MFD in tight situations. Don't have to buy a bunch of extra weight to make it do the same work, etc. Got any more things you can make up?

If you're trying to compare a 4wd to a 120 hp loader or haying tractor it's a different story. That's not what's being compared here.