There are many variations. If a provider requires a deposit and then ghosts, what then? As for risk of being assaulted, read the thread about the guy who got pistol whipped by a pimp and robbed for everything in his wallet. Is that not a risk? So saying that we don't have to deal with risk while engaging in this hobby is not being factual. Also, at a restaurant if I don't pay I have stolen product that could have been sold to someone else. The service you provide, if not paid for, is just theft of time. I have my time wasted regularly and I can't have the perpetrator charged. At least if it was legal you would have a basis for chasing after payment for all the no shows and false bookings that are constantly complained about.
I will gladly acknowledge the fact that I didn't base my numbers on any real statistics because you will never find 'real' numbers to use. I'm sure that, much like the number of rapes that are reported, the number of assaults/robberies of Johns are under reported. Even on a site like this one, I'm sure that most members would be too ashamed of what happened to own up to it.
IMHO, sex work should absolutely be legalized. Screw the whole 'decriminalized' crap that is spouted. Make it legal, invoice it like any other business, and either build in the HST or have it added on as it is with any other service out there. I think there is a strong argument to be made that a regular sex life, paid or otherwise, is essential for mental health. Intimate connection with another human being is good for a number of things that I don't have the time or inclination to look up right now but I think it would be a net positive for the government to legalize it. Collect their HST and allow individuals to claim it as a medical expense.