Porn Stars
It really depends on how you approach it. As I mentioned in the post above, I approached Kayden by asking her if she would film a scene with a fan. Her vehemence in her refusal left no doubt in my mind as to what her answer would be if I asked her to escort.
On the other hand, at the same convention, I ran into about 6 different porn stars, none of whom I'd seen before, and all of whom I had discussions with about the hobby. I've partied with 3 of them since the convention.
Btw, 2 of the 6 approached me and brought up the subject of escorting based on my commenting only that i wish I could be one of the lucky guys in her films. With one of the 6 I talked to I hadn't actually said anything to her before she suggested it to me after I gave my name while she was autographing. The conversation went something like:
"Who do I make this out to?"
"Mr. French"
"Are you the Mr. French who dated [name withheld]?"
"Um, yes. While she was on tour in Manhattan last month"
"She told me about you"
"It's all a lie!" [with a smile, of course]
At that point, she autographed a picture, took one of her business cards, turned it over and wrote on the back the name of the hotel she was staying at, her cell-phone number, and the rate per hour she was offering me and just handed me the card and winked. Sometimes it's nice to have a reputation. 
That isn't the only way I've approached women. There are other ways. It depends on the woman, and how many guys are lined up waiting. If there's a long line, I try to keep the conversation short and discreet and usually only ask about her work but come back later to ask about other stuff. It varies.
But, you'd be really surprised at what can happen at a convention and how things can go in conversation. I remember asking for a picture from one porn star. She insisted for the picture that I stand behind her and hold her breasts. When the picture was snapped, I said something like "I suppose I have to let go now, huh?" and followed with "I don't suppose I could join you in your hotel room later to fondle them some more, could I?" Her response was: "Come back a few minutes before the show closes and we'll talk about it." Unfortunately, when I got back to her booth 5 minutes before closing she had already left. Sigh.
Also, another pornstar simply said to me (and everyone else in line) that she loves having sex with her fans and if I was interested to contact her through her website.
Beyond those instances with UTRs, I had open but discreet conversations about the hobby at that convention with: Teri Weigel, Christy Canyon, Sunny Lane, Bree Olson, Sara Jay, Vanessa Naughty, Ginger Lynn, Taylor Wane and a few others I can't remember now and a couple I can't mention because they're delisted. Not all of those ladies provide, btw. We just talked about the hobby in general.
Just like approaching women in a bar or club to ask for a date, you have to size up the situation and the person, engage in some conversation, and be someone she likes rather than someone she's afraid of or someone who disgusts her. Each woman is different. Each guy is different. What I described above worked for me but might not work for you. And, what worked for me with one woman probably wouldn't have worked with another. I know my techniques didn't work with several women at that convention. I shudder when I think of my conversation with Amy Fisher...
I'm sure if FastEddie were still here, he'd have his own stories to share. I remember meeting him at a convention when we were both hitting on the same model. He had his style, I have mine. I didn't succeed but maybe he did, I don't know.