Why are there so few blown small blocks?

I think the lack of roots blown mopars has a lot more to do with the cars than the engines. To most people Mopars are muscle cars, plain and simple, 60's and 70's. Roots blowers are a rarity on any brand muscle car. Yeah there's a few, but very low percentage wise. The overwhelming majority of roots blowers are on old iron(rods, buckets, Willies, Anglias, tri-5's, etc), and very few of these cars have Mopar engines. I really think it's as simple as that.