I'm sure they're all HPV infected, and I agree it is likely that overt warts are a common occupational hazzard. But I'll also bet that they are on top of it and that expert treatment is readily available. At least herpes can be treated to prevent outbreaks and transmission, so I'm not sure what to predict about HSV-2 and genital herpes. My understanding is that the porn industry, at least in So. California, is pretty well organized and cognizant of the health risks, and that employers (and the health department) require regular HIV testing. I would guess routine testing for other STDs also is common. I can't comment on how much the workers themselves know, understand, or care about the risks.
Regards-- HHH, MD