Yes, I can see your point. and of course, it may be a matter of principles. I don't know what you drive in real life or what you had as a real car, but as a brazillian like me, you know our internal market is full of bad and weak cars and for those here that aren't "rich" we must have fun and "survive" with what we can have. I started driving on a 1.0 liter Fiat Uno as my first car (58hp and it used to go up to 7200rpm)... and God, it was some of the funniest moments I've had in my life. In weak cars, you need to perfect your driving, your gear changes, everything because every second you lose does have an impact on the car "performance"...
Weak/small cars are an excellent school for beginners imho and that's what most people can drive in real life, so I think they're important because that. Not everybody can drive a sports cars with ease, so why not reflect in the game, a situation that you my find in your garage? Your parents economy car or your first, cheap car... you know, in Europe, Japan, Australia, US you can buy an used sports cars or something with good potential for low money. But for those like us, that live in countries damned with high taxes and shortage of sportscar options, replicating something more "real" and plausible, it's an awesome thing.
How many times I drove the Corsa Sport (Corsa B) in GT2, painted in white, just like my dad's car was? That was super fun!
Like I said, I just think we can have it all BUT, a good balance must be respected. We need more sports cars and less of these economy/small cars but we still need them in the mix imho.