The reason why is because she has NO traits of a GSD, except the black mask. And as I have read in my research of the breed many people are not aware of the belgian shepherd breeds, and therefore, their untrained eye sees the mast and the pointy ears and assumes it is a GSD.
The person I got her from was just a normal dog owner (of my pup's Mom, a full bred Yellow lab) who doesn't really know much about dog breeds, and she took a guess at the breed of the neighbor's dog when she saw it humping her Yellow Lab one day. But none of the pups have any of the common physical traits and 3 of them have classic Malinois personalities. (I actually happened upon 2 of the other pup's Mommy's on apetfinder forum.)
My pup in particular has many of the common malinois traits, both physical and personality. You can see the lab genes in her head: her lips are droppy like a lab, and the nose is a tiny bit rounder than a typical Malinois.) She has the extra furry part around her neck, which Malinois have and is called a "collarette", she has the deep but not broad chest, she has the mask, but really no major black anywhere else (GSD tend to have black on their back). She has the black tipped fur kixed in around her coat, especially her tail.
I could go on.... but, there is also a large K-9 training facility in the state I got her from. Many dogs that go to K-9 don't make it all the way through for various reasons, and the training centers usually adopt the dogs out to the area. So, even though in general the GSD is more common, my pup came from an area where alot of Malinois dogs are adopted out to families. I also bet that the Malinois, and Malinois mixed dogs are alot more common than people think. I did a quick Petfinder search for the breed in my region and it found several hundred Mal mixes.
