Why is porn considered as a form of sex trafficking?

I read online that porn can be a form of sex trafficking. I find that hard to believe because they are giving the men consent to have sex with them. If they were raped that would have tears going down their face. Also they would run the risk of being rescued when they are seen on the internet. I saw that a woman was giving oral sex and the men were having sex with her. At the end they were interviewing her and she was laughing about it. That can't be sex trafficking because she gave the men permission to do that to her.
Answers

Pascal the Gambler

It isn't.

linkus86

Its not per se, but when its used to promote sex trafficking it is.

Kat

It's not normal to have sexual relations with strangers and be paid for it. It's called prostitution. The fact that pornography features extremely young women who might not yet full understand the emotional and other long-term ramifications of the job means that the potential for exploitation is high.

Edwena

You make the erroneous judgement that women know what they want. It is the same as drug dealing. After people are involved, they would like to not be involved, but are trapped into being involved.