Questions about 4-wheel drive vehicles

I got a few questions about four wheel drive vehicles:

-What is it about them that causes them to get less gas mileage than 2 wheel drives?
-Is there a way to take the S*** out and have it converted to a 2 wheel drive vehicle?
-If you do take the four wheel drive out, will it get better gas mileage? (Like that of a 2 wheel drive?)
-Why did those stupid motherfudgers from Chevy only make 4 wheel drive crew cab S10s? It wouldn't have hurt to have some 2 wheel drive 4-doors S10s as well. :mad:

Just my opinions...

"-Less gas mileage"
The 4wd trucks are sometimes geared lower.
The 4wd trucks have more weight due to the transfer case and the front differential
The 4wd trucks are spinning more weight with the front axle half-shafts turning all the time.

"-Is there a way to take the S*** out"
You could remove the front differential and both axle half shafts to reduce the weight and also reduce the spinning weight. You may have to leave the end of the axle (the part with the splines) in the hub to keep it properly sealed, I don't know.