Because I love my driving iron. Ancient Mizuno Pro 2 iron bent 2° strong. Not only does it get me in the fairway, but if i am in trouble, there is no club I can carve more with. It gets through anything, and the only time I hit it in a fairway is when I am taking a risk and going for it on a 600yd+ par 5. I would love a modern version of it, but I have trouble getting stores to even order me the MP-20 with the shaft I need.
Is it highly practical? I dunno, probably not. I am sure a modern utility club could do much of the same, but it is a confidence thing. Out of the woods, in the tall grass, or into the strong wind I know I can get out of the situation. I just cannot get the utility irons low like I can my blade.