That applies to so many jobs and people, it's not funny.
And as far as "exploitation" goes... what about child labour in third world countries or worker exploitation (and consequently suicides) in China?
Yeah, and I don't like it that it happens there either.
But it's like having a legal multi-billion dollar sweatshop industry in the West. Again, not saying it applies to everyone involved in the industry, but some people who do porn and then want to move on with their lives have that experience hanging over their heads (and it's not likely a pleasant one from their viewpoint), and they know that at any point, some guy or girl out there somewhere is going to be watching that moment and getting a thrill out of it. Especially if it's on the internet, because once it's there, that **** stays there.
And while it doesn't apply to everyone who watches it, people do get addicted to pornography. Their fantasies get more and more elaborate, and the need to live out those fantasies overwhelms, say, the need for a meaningful relationship. And if they do ever get involved with a significant other and still have those fantasies, it can end up hurting that innocent person who neither watched nor participated in the porno.
It's like anything else you can get addicted to; if you let it get out of control, it can ruin not only your own life but others' as well. People will watch porn no matter what I say, but I'm not going to have any part of it.
Well devils advocate again: Some people eat too much chocolate/fastfood etc., grow fat (certified relationship killer) and even die from adiposa.
(Not even having mentioned what happens when you too many consume cigarettes or too much alcohol... how about an alcoholic beating his children for hurting innocent bystanders?)
As far as the multibillion dollar corporations go... you could even argue that the American porn industry has "some" moral highground (we would definitely have to look at individual companies and practices here, as likely we both are right - and wrong - depending on the company) as it doesn t participate in aggressive offshoring and low wage country exploitation quite as much as some other companies do that you certainly already bought several products from.

Just look at the stickers of the components in your computer and we re likely to already find several culprits lol.
Also... keep in mind... while the "worst case" conditions may certainly be dire (but so they are in several other industries)... there is a rather significant difference: if you look for the most successful "sweatshop workers" you are still looking at a poor sods who can t afford anything... if you however look at successful American Pornstars, you are looking at a millionaires who are able to afford an ultraexpensive lifestyle. The Sweatshop analogy doesn t really fit... or rather focuses on a very specific segment of that industry while ignoring everything else.
In summary: Anything can be dangerous if it gets out of control, as you yourself said. Furthermore, there are also businesses that exploit humans in need just as much or even much more than the porn industry.
Addiction needs to be avoided and exploitation needs to be shut down no matter which industry it occurs in (and good luck with that, with even Apple being guilty and a huge percentage of other computer parts being manufactured in low wage countries as well)... so why does porn deserve special attention other than .... "but but but... it's naughty!!"
