In all seriousness, it's about time that prostitution was examined with the same critical eye we've finally started to turn on cannabis prohibition. The results may (and should IMO) be similar: ater criminals are cut out of the loop, both the dealers and customers end up better off, as do the tax authorities.
In that eventuality, yes, mobile service would obviously be at least as lucrative as van-based barber shops, probably far more so.