Probably because no one wants to get near the thing and because it's dark out when it's spotted. I could see why no one want to get near it. It looks like something out of a cheep horror film.
Just think about it: You're walking down the sidewalk at night when you hear the faint sound of foot-steps. They stop as soon as you turn around. You continue walking, thinking it must be your mind playing tricks on you. As you turn around a corner you here the foot-steps again. As you turn around you see a small shape run back around the corner. You decide to investigate, going back around the corner. Then you see it. I tiny man wearing a pointy hat, a sinister smile across his face.
Could you honestly imagine a more horrifying, not to mention akward experiance? Next thing you know, there will be more of these guys waddling around, attacking people. Some may even begin riding on small pets for transportation.