I'm not from Saskatoon, but I can read their bylaws.
City of Saskatoon Adult Services Licensing Bylaw -
http://www.saskatoon.ca/DEPARTMENTS/City%20Clerks%20Office/Documents/bylaws/9011.pdf
City of Saskatoon Zoning Bylaw -
http://www.saskatoon.ca/DEPARTMENTS/City%20Clerks%20Office/Documents/bylaws/8770.pdf
And from The Adult Services Licensing Bylaw, 2012:
So even an independent SP, if she advertises in any way, is an adult services agency under the bylaw.
Back to the Zoning Bylaw...
Now we look at the Home based business section of the Zoning bylaw...
So, the lady in the article that has had the city police come by telling her she needed to get a license is in a very tight spot:
Don't get a license & keep getting harassed & ticketed. Or obtain a license.
If she can be issued a license, and she wants to work from home, it cannot be an in-call. She must work out-call only. If she wants to have an in-call, if they would license her for one, it has to be at least 160m from any residence, school, park or recreation facility.
That is how they would push her out: by using the zoning bylaw.