Have they got no shame?

[SueEllen]

They are the Queen's tax collectors and as such the Queen will be committing a criminal offence by living off immoral earnings.

If morals are wrapped around legality than being a sex worker is moral but applying your trade in particular ways e.g. working in a brothel, soliciting on the street are illegal.

In other words they should pay their taxes as what they are doing is legal.

[EternalOptimist]

miss whiplash,
when I have finished cleaning the kitchen floor with me tongue,
I must ask you
are you subject to supervision, direction and control ?

[AtW]

miss whiplash,
when I have finished cleaning the kitchen floor with me tongue,
I must ask you
are you subject to supervision, direction and control ?

Nice try, but it won't work since they've got multiple clients and engagements are short...