I agree with you about the purse not being a place for a woman to pack. However, I work with a sizable population of women who are plain clothes/professionally dressed LEO. They do complain with regularity about practicality, fashionality, and concealability (hips) of holsters that are worn on the waist line and even the ankle. They do it, but I can tell you they don't like it. IWB seems to work well for some and a couple with slender hips pull off the owb with success. I say all that to say that it comes as no surprise to me that some women not in a LEO choose the purse. Just an observation.
I know Jon and others have more experience working with women in an instruction role who could provide some more insight into this.