wander said it best: "Almost all want Price charming to take them away"
I find it somewhat common that the newer or more inexperienced WG's fall for a john if they're just treated with respect and kindness (and I guess it doesn't hurt to be above-average looking and speak the language). Unfortunately (or fortunately depending on how you look at it), its been my experience (personal and observed) that most of the time it just straight doesn't work out and is a plain bad idea. Think it mainly falls to trust issues on both sides; the WG will continually hound you to see if you're out mongering if you're not with her, and there's always the thought in the back of your head that she's still after money.
Of course, both are easily solved by stating clearly what is or isn't expected should anything actually happen between the two, as thebigz0 says. Think it's also important for us punters to realize that fair's fair, and if we establish 'rules' for any sort of relationship, they are free to do the same (ie: using you as a personal ATM machine).
On a related note on this topic (seems like the place to write it up, as its not really a report on anything specific):
Very recently celebrated an awesome birthday with two of my regular WG's who I believe have 'fallen' for me.
Day 1 (day before birthday): WG #1 called me in the morning to say happy birthday. She then asks if I can visit her, to which I let her know I was feeling a bit tired and just felt like staying home. She then asks permission to spend the day with me, and tells me she'll call off work (fine of ~500RMB) to be with me... I actually told her she should just work and not get fined, but she won't hear of it, so... OK! Comes over around 3pm, looking pretty scrumptious in her regular clothes (hooray for hot weather and short shorts!) and greets me with some nice DFK. First round followed by an hour of rest, then try going for round 2 but unable to pop (the feeling tired part wasn't a lie) so then shower, and head out for a quick bite to eat. She insists on paying for dinner as well, then afterward head back and have a successful round 3. Told her I had to work early the next day, and she was fine with leaving. Tried to at least give her money for what she would get fined at work, but she wouldn't take it. Happy pre-birthday mtmtmt61! heheh..
Day 2 (birthday): WG #2 sends me a text wishing me a happy bday. Reply to her with a thanks, and then she sends me a text asking if she could come over! I did a double take, making sure I was reading the right text and not the one from yesterday. Checked the date and sender, definitely a new one! I ask her what about work and she says she'll come over after work, and that she needs to give me my present
She ends up getting off work about an hour early and comes over. She first gives me my present (brand of cologne that I use, think its around 800RMB here), then asks to use the bathroom for the second part of my 'present'!! Turns out she bought some knee-high socks, of which I have a huge fetish for, and off we go for birthday sex! We wake up around 7am the next morning for another go, then sleep again til close to noon, at which point she goes to work. Again, tell her she shouldn't have bought me anything, and offer to pay at least for the cologne, but she gets a bit offended and says she doesn't want anything from me but, well, me.
So all in all, a great birthday filled with freebies!