And for me, the bottom line is...
...legalized prostitution, or at least decriminalized prostitution, may result in less brutality against the women and girls who are in the low end provider part of the business, because they could organize, buy insurance, and develop professional standards, including age restrictions, like any other workers. Right now, they're in the same exploitation cycle in which many illegal immigrant workers find themselves: either put up with their own exploitation, or report it and face legal action themselves.
The girls working for the Emperor Club don't face physical brutality -- they're not worth anything bruised, just like any other consumable fruit.