Whats the deal with the black rear facias on some Camaros?

Some Camaros have a black rear facia just above the rear bumber. This is also the facia that has "Camaro" embossed in it.
Did these come from the factory or is it some custom paintjob?

The GMMG built Berger Camaros had this done. People like it so the do this to their ride.
GM blacked out this panel on their big block SS rides back in the 60's and 70's.

The Poncho equivalent would be the Ceta bumper.