It's the Swedish model and it's been widely discredited. Good point re porn - there's a family guy joke about filming your session with a hooker and it's legal.
The police aren't really interested in sting operations for harmless non crimes with trivial punishments, so I just think they can't prove what goes on between closed doors. We can all invent some daft dark but legal kink, like eating strawberries off each other's, holding hands, enjoying a glass of wine, going for a long walk beside the sea, or paying a WG for a third rate massage. Then all just pretend customer and specialised service provider really fancied each other in, and couldn't help having sex, right there and then. It's no different to paying to view a property to let or buy, then ending up fucking a hot young fit estate agent hard and nasty over someone else's bed, for being the scum of the earth. And she was in to that too, your honour!
I've just saved punting from Harriet Harmen, made estate agent's lives a lot more awkward and spawned a new fantasy for myself, all in one night too. You can all say thankyou by going down on your local hooker.