pain in the ass, just say what it is you mean to ask.
To answer your question, yes. I have walked away when I saw that the girls was clearly not the one in the pictures.

One other time I was already in the room before I realized this was not going to be working out as she laid down all her rules and gave me a shit ton of attitude. At that point I told her we were both wasting each other's time and gave her a 50 as I walked out. I will also say that this happened after many instances where I DID put up with t and went through with a shitty session because I didn't stand up.
I felt more empowered to do that after a few years of experience.

I have heard horror stories where the pimp shows up and demands full payment.
Stay with well reviewed ladies with good reputations and you'll rarely encounter such problems.