I don't believe the issue is people not caring. I believe it is, as one poster put it, you don't flare the fenders on a '57 Chevy.
I opened this thread to say exactly that. It looks really unorthodox. But hey, if that's what floats your boat, more power to you.
Having said all that, I was also going to tell you what I learned from Mark Gustavson's old "Custom Clinic" series; glue a thin strip of plastic to the wheel cutout and fair it in with putty, although this is really more for new fender lips rather than flares.