They don't.
You hit home with that post. I remember going to a show at Silver Springs in FL (years ago) and seeing a "restored" FHP car there. Not a single piece of equipment was correct, but it was definitely "showy".
There are guys out there that just want "blinky functionality" (and attention), and others who want to restore their vehicles correctly. Thankfully, more of the latter participate here, 'cause that's what we're all about.
That Crown Vic is absolutely beautiful. Wow.