Bonsoir dcfan
Driving escorts or strippers is the same for the law. You can not legally transport somebody for money without the legal papers. That is transportation licence, taxi permit, plate and insurance. It is not only the cop who can stop you. You can be arrested by the Montreal taxi permit regulation group (I don't know exactly the name) or by the provincial road controllers.
Penality is a very stiff fine. It can also include a severe beating if some legal taxidrivers catch you in a dark alley. It can include the car getting confiscated permanently if I recall correctly. It will be in-pounded on the spot guarantee.
Driving escorts versus stippers is not the same, I should know I am a lawyer. The first will get you a criminal record, the second won't (unless you drive them where they have sex with client which makes them escorts and not stippers anymore)