If you can get a V6 to do a job a V8 normally does why not do it? For example take the GTR and compare it to every single V8 car for the same price.
I really don't see anything "funny" about it, I think it's sad that a V8 car with equal performance is twice as expensive.
the gtr is stupidly higth priced, and would actually serve against your argument due to that single factor.
now, if you take the camaro 3.6 liter, or the ford 3.7 liter, at 312hp(being pumped to 323 soon) and 305hp(also being pumped soon) respectively, both in common production line built cars that the average joe can buy, then you've got a different story.
you can roll in a 13 second mustang six banger for $23k. you can roll in a low 14 second camaro for nearly the same price. both of these cars easily outperform virtually ALL of the common "hot rods" of yesteryear. they do it in virtually every way.
now, i know someone's gonna come on here within the hour of this post going up, pointing out the yenko camaros or novas, or the thunderbolts, or the 10 second mopars......but the mopars, and thunderbolts were bare bones cars, with not even a radio installed, the yenkos weren't production cars, and none of them were common cars.