Didn't Chemical People use porn actresses as cover models for their first two or three albums? Not too surprising, then, that they'd provide the soundtrack for a film that involved Ron Jeremy.
And I can't speak for anyone else, but ummm, no, my "youthhood" didn't include any experiences involving any porn star. (I did once see a flick that included a woman I had worked with -- in an, ummm, active role -- but the company we both worked for had nothing to do with porn.)
A girlfriend of mine had done a couple bit parts in regular movies (crowd scenes, etc.), and when she got the chance to do it again, she encouraged me to come with her and be in the film too. I declined, though. From what she'd told me, a day of that work involves a lot more waiting than acting ... and I would've had to take a day off from my regular job to do it. No thanks.