My experience
Great thread! It's a rainy afternoon in Ft Lauderdale and I just wondered in... some TERB old-timers... at least Fred and Shiek, will remember me from past visits to Toronto, one of my AFT cities!
Now, it happens that multi-day trips with ladies are my "speciality" and I've seen both sides of the pricing argument, and I believe a lady's position on it often depends on why she's in the "biz".
A1 (I'd love to know who she is... I love "fiesty" women) argues for keeping the high posted daily rates because, as she points out, she's a "professional" (in the best sense of the word") and there are a lot of unseen costs to the biz. Further, and while she doesn't say it, the high daily rate keeps out the riff-raff and provides compensation insurance for the occasional lousy time. To my knowledge, the most common full price dates are when the lady has never met the guy.
Shack's Lady X may be more casual to the biz... it's a way to pick up extra money and maybe see some of the world, as she did with Shack. And, since Lady X knew Shack from past encounters, so she knew she'd have a good time and didn't need the "insurance" pricing.
All service businesses are going to have different prices for the same task. If you get you car fixed at the dealer, you'll pay more than at the local garage, and still more than at the neighbor who fixes cars in his driveway. The dealer, of course argues all should charge his rate.
As I said, I've had quite a few experiences with trips. Until this year, I never travelled with anyone I hadn't spent a night with, but this year I've had all good experiences based on a pix exchange and a few long phone calls. I do have a life-style some think is a vacation... I'm single, live on the water with my boat out back and have a home on my name-sake island. And, I'm a well-known TBD poster on the East Coast. I tell you this as it may factor into the pricing. I've had ladies in the biz travel with me for prices ranging from nothing for a weekend to US$800/day for a week. Of course, I pay all expenses ... and the lady that was for nothing got a US$635 pair of shoes she "had" to have

)
Here's a recap of a few of my trips (all with women between 28 and 36, so naivete isn't in the picture):
March 2001 a blonde (now retired) from Toronto came for a week on the boat in Ft Lauderdale (before I moved here) and the Keys for C$1,000/day. We had spent a weekend together in Toronto, which was preceeded by about 50 pages of emails, so the rate reflected our "clicking". The same lady came again in May for a trip to Bimini at the same rate. She then had a friend visiting from the Far East and wanted to bring her for C$500/day, plus expenses. How could I say "no" to a week long 3-some? Death by blondes, I called it.
Later in the summer, and after posting an ISO First Mate on East Coast TBDs, I flew several ladies to Boston for "interviews" at US$1,000/night to see who would join me on a New England cruise. The rate I offered in my post was $500/night and the winner, Meredith, posted this review (follow the link inside it to my review of the trip):
http://www.bigdoggie.net/messageboards/miami/msgs/posts/26354.html My posting the rate upset several ladies in the biz, just as A1 is upset, and they prevailed on TBD to take it down. OTH, several ladies posted that no one had to respond if they thought the rate was too low, and that they liked the vacation-with-pay concept.
This year I've had several ladies that started out "on the clock", US$1,200 and US1,600 a weekend, then go off the clock after a few visits. No, we didn't fall in love, but they felt we had become good friends and didn't want a money-based friendship. Next week a lady arrives from the West Coast. She lists on her site a "monthly girlfriend" service that involves 1 weekend, several long dinner dates and several afternoon sessions for US$2600 a month. She's coming for 10 days at this rate because she wants to see both Florida and St Bart (the island).
So, that's my experience. Hope its useful to the discussion.