Like Tina, I usually don't require references for meetings, but I have occasionally checked them in the past, and am always grateful to the lovely ladies who give them to me.
I don't really get how some of you can't understand why references are so necessary. I also don't know why anyone would find it uncomfortable. We aren't in competition with each other, almost all the SP's I've met have been extremely supportive and respectful to each other, so they are in no way going to be upset to learn you want to see another lady. It's not a secret, we know you see other SP's, we know we aren't the only one, so we aren't going to be hurt if you politely ask if they wouldn't mind giving a reference to another lady.
We are putting ourselves more at risk than the men every time we go to meet them, and so usually a reference is a nice way to smooth the anxiety, and it let's the lady know that the client she's going to see is a respectful gentlemen, and probably won't murder her.
As for newbies who have never seen anyone before, there's a pretty simple answer to that. Most SP's that require references will have another option for men who have never seen anyone before, some will ask for a deposit, others may have different options in place.
I'm not sure about you guys, but I find communication online, by email, or by text, doesn't always showcase who you are in person; tone and words can be misinterpreted or you can just be bad at writing, but be an otherwise lovely person. So sometimes it's hard to tell what a person is going to be like when you meet then, and if you're unsure, a reference can be a good way to be reassured that they are a great client in person, but just really bad at communication.
All-in-all, while I don't always require them, references can be very useful.