Store banning CV19 Vaccinated customers?

So some businesses are banning people who haven't been vaccinated but here's a business in Windsor, Ontario Canada who is banning those who [b]HAVE[/b] been vaccinated from entering their store? What am I missing here?

https://windsor.ctvnews.ca/windsor-ont-store-posts-sign-barring-those-who-received-the-covid-19-vaccine-from-shopping-inside-1.5390844