stigmatization

This is a question that's been bouncing around in my mind for a few days:

"Would sex work be so profitable if it weren't stigmatized or criminalized?"

Sex work is often an attractive option for single mothers, because they can earn more money and (sometimes) work fewer hours than they would at a retail or other service industry job, thereby allowing them greater economic stability and more time with their children. But to what extent is this attributable to the stigmatized – and, with prostitution specifically, criminalized – nature of sex work?