Alanah Ramos is very fun and provides cof.
I dont know if any of the WCA girls do, but i woukd imagine it might be available, as well as some of the other outlook girls.
Im hoping someone else has other info on WCA or outlook!
It is rarely offered because it can 1) irritate the eyes, 2) mess up the hair, 3) seem degrading.
I agree with you in the sense I wouldn't mention it publicly if I'm not sure the girl wants it to be known.
When it is advertised (rather than possibly a secret bonus to a client), thinking of it, there's less YMMV factor in it the way Greek or CIM are often YMMV.