The good thing about using private security is that you can ignore anything they say to you. They only have the power to contact the police. If any security employee lays a hand on you that is an assault

That's not true. They can make citizen's arrests and they can use force to do it.

https://www.cbc.ca/news/canada/security-guards-secure-right-to-use-reasonable-force-1.390907#:~:text=Private%20security%20firms%20are%20applauding,when%20making%20a%20citizen's%20arrest.