No, Ontario doesn’t have a Moutain Street. This tile shop on Mountain Avenue is presumably better at fitting tile than in fitting all the letters in Mountain into a cramped space. The mistake is repeated on the other side of the building.
“Moutain” — which I would pronounce “moo-tahn” — doesn’t mean anything, to my knowledge, but the word reminds me of poutain, the Canadian version of French fries that comes with cheese curds and brown gravy. Wonder if the Chaffey brothers would have liked that?