More or less the same reason why tropicana doesnt price match a lemonade stand. You are getting a much more reliable service with Koodo. Once wind has a network that is actually functional, Koodo will compete in price. As it stands, wind is not very good and isn't even considered real competition.
Unfortunately Koodo only match their price with FIDO and VIRGIN because they are similar in nature and their services are almost at the same level. I think, maybe, Chatr, Wind and Public Mobile will do price match with each other.