Actually Goldy, Black Dog Syndrome is a real thing and I'm guessing that's what they're attempting to counteract here with their special "Black Friday" promotion.
Black dogs (and other animals, I'm guessing) are often the last to be adopted for a number of factors. Some of these include:
-fear/superstition about black animals
-black dogs are not as easily photographed (think about online adoption sites) and don't stand out as much in poorly lit kennel areas
Google it and see for yourself. Here's a good link to start with: http://www.blackdogrescueproject.com/bla…
And then go adopt a black dog.