When you describe more about her seems to give more indication of her personality or she didn't appear to hide how calculative she could be
I've had great regulars, when you get down to it its about money but there are the small things like not time watching. Its a better feeling when you can message them personally as it feels she is treating you individually and privately outside the shop's management.
Even from just making money stand point, treating you so obviously like that makes no sense as you would quickly lose a regular. I think she must have gotten away with this bs with other regulars who put up with it or was she really that popular?