In Brazil there's an agency called ECAD which already does that. However, the fees can get much higher than those mentioned in the article. Sometimes agents from ECAD show up at weddings and charge a fee based on the number of people attending it, or based on the physical size of the room, or as a percentage of the price paid for the rental of the place where the wedding is happening. It's common to see couples having to pau more than US$ 1k on that.
There are many cases of people who didn't have cash to pay when ECAD agents shown up on their wedding, and who were then ordered to stop the music and the event. They are very frequently sued, but yet they continue to charge that (and get richer).
Hopefully the same won't happen in Canada.