This is totally false. The pug is one breed, black or fawn, a pug is a pug. Both double coats, therefore, both shed just as much. There are alot of pug rumours in the world and I would like you not to believe half of them. Shedding can be taken care of with a regular brushing once a week. Watch out for health problems and ticks and fleas, and grooming should be an enjoyable experience for both the owner and the dog. I know someone who owns a pug, and she is the healthiest dog in the neighbourhood. Sheds just as much as a fawn pug, and just as friendly. Remember, no matter the colour, it's the same breed, the PUG!
I have a black and a fawn pug and yes, the black one does not shed nearly as much hair due to the single coat.
I raise Pugs and a lot of black Pugs have single coats and do not shed as much as fawn Pugs with double coats. Of course some black Pugs have double coats too and shed as much as some fawn Pugs. But my experience has been that in general blacks do not shed as much as fawns.