When is an "M" a "W"?

Sign at Centra Windows location, Grandview Highway, Vancouver, BC

Sign at Centra Windows location, Grandview Highway, Vancouver, BC (Detail)

Sign outside Centra Windows location, Grandview Highway, Vancouver, BC

You'd think that a firm that sells windows might make sure that there were enough "W"s on hand for the signs. But in place of "W"s. the firm is using upside down "M"s.

Would many people notice a small detail like this? Probably not, but to my eye its just looks odd. An easy mistake to make, and an easy mistake to fix. I wonder why they don't fix it?