I found these 3 things on shops, they are quite interesting...
You already may know this one, a shop, where in the window you can see a guy with a bloody apron, holding what looks like a dead child. Leatherface?
The next one is interesting, it's in an antique shop window, and it's a guy in red ceremonial robes holding.. A CANE! Chris Fromage anyone?
last was a sign on a mask store, maybe a hint to hidden myths in the game? we know that there are rare clowns, but maybe witches and aliens too?
I'm going to keep looking around for more interesting shops.