This girl sounds psychotic.
I'm mixed race and won't see black guys, or anyone who isn't white and speaks clear English.
That wasn't the initial plan, although I was reluctant to see Asian guys due to personal preference (not a full timer, want to enjoy it while I do it, better for everyone involved). However I didn't rule anyone out.
Now I do so simply because it has caused me a lot less hassle and personally it makes me feel more at ease.
I haven't had the misfortune of meeting anyone horrible, only dealing with them via AW messages or telephone.
Only black and Asian guys have tried to haggle my rate - "you're a bit expensive", "I only pay to see stunning girls", "you will give me a discount because you know you will enjoy this African d*ck (because you're African and know we do it right)".
There are BB and boundary pushers all over AW, but the only ones who ring me rather than spam me on AW are Asian. One is currently stalking me for refusing to meet him 3 times for telling me I'm going to provide a service I don't offer. Sorry I'm not trying to get all SAAFE on you, I do have an eventual point. This guy made me change my policy, as he rings from so many numbers I don't want to risk meeting him by being tricked.
The only potential customers who have turned especially nasty when arranging a booking (usually discussing services or rates), calling me abusive names on the phone or by text... are black and Asian.
From my limited experience, sadly it seems that more Black/Asian guys (especially non English ones) project an attitude which seems to imply "you charge for sex, so you are a dirty whore who will do as I say". Whereas a good punter will look at a girl and her services first... more minorities than white guys will ring the girl and expect her to do everything, as though she hasn't a choice because she's a prostitute.
Don't meet anyone who's not white, I state it on my profile... cuts out the hassle. Sad because I wouldn't ever want to be considered racist but c'est la vie.
I'm sure this doesn't apply to every WG's reasoning, but I suspect it's quite common.