Okay, here I go again. I have worked in the porn industry, mostly in Post Production, but have done a very small amount of on-camera stuff as well, mostly stills.
It IS an industry, complete with distribution networks, overseeing bodies, conventions/trade shows, and all the other attendant aspects of any large industry. It also has various federal regulations to comply with, such as U.S.C. 2257 and maybe a few others. The actors are almost always hired from professional porn model agencies. Only rarely does a true "amateur" film get made and released, considering the costs of production, replication, advertising and distribution. And there are only a few distributors with the ability to get the films out to the stores or other marketplaces.
Now, while the work on the set is generally very professionally-handled, occasionally you'll see two people, sometimes during a scene, sometimes between shots or takes, getting personal in terms of fucking each other, and suddenly it becomes very real and intensely erotic. If you can get that on camera, it is almost always obvious and VERY arousing. However, most of the time on the set the actors and especially the crew are just as professional as any other area of the film industry. They have to be: they're there to DO A JOB for which they are paid, and that's not to have fun sex. It's to make a film of people having sex. There's a difference. Granted, it can be really fun, sexy, HOTTT work, but it's STILL WORK.
At our shop, we did Str8, MILF, Gonzo, "Amateur", Tranny, and some Gay porn.
In Gay porn, some of the guys are naturally slutty and will do it with you off the set, although that's frowned upon by the pros unless it's done later, at home. Some of the guys claim to be straight and are only doing it for the fun or the money. They are called "Gay for Pay," and are not well-respected in general. There are also people on-set in some productions, called "fluffers." Their job is to suck the cocks of the males who are supposed to be hard for the filming before they go on-camera, in order to get them "up." Viagra is often used by the guys to stay hard. This of course can have serious health consequences, and is one of the more questionable aspects of the work.
The shop I worked for was a small one in Palmdale, CA. Only very rarely did any of the actors come in. I did offer to suck off the UPS driver once, though. He declined.
The work I did was the editing of the films and the authoring of the DVD's. This was the largest job on these films other than the shooting of them. We did American, Brazilian, and European films. The ones from Europe usually had a big budget and very full production values and techniques. The American ones were pretty raw by comparison. Somehow, that makes sense in America, as we're so prudish and Puritanical about free expressions of sexuality that it's no surprise that many of our porn films have a rather furtive or cheap quality about them.
The Brazilians even had custom-filmed helicopter shots! As well, they had universally the prettiest actors in general.
Anyway, it's a job, and I found it to be routine in many respects. On certain days, though, a film would come in that was so hot I had to lock my edit room door while I worked and J.O.'d at the same time. The best part of the job for me was it was a tiny shop, just me and the owner, and he was a very nice, relaxed person who allowed me to J.O. in my office if I wanted as long as I got the work done. I was allowed to openly smoke pot (I use it for my AIDS drugs side-effects) as long as I blew the smoke outside. If I needed a short nap in the afternoon, we had a nice couch in the front office with my name on it. And, best of all, the boss encouraged my graphic and editorial creativity, and we meshed quite well, and I gave his films a fresh look that he had been missing up to that point. I have since worked on a few "legit" documentaries and features and pilots with him. I must have edited at least 30-40 feature-length adult videos and DVD during that time.
So, my experience in the three years I worked in the adult industry were nice.
But not everybody has the same experience.