It is a business that they want to grow. As always with businesses, they will negotiate with their customers if they see a long term benefit. Of course, the scope for negotiation depends on the working woman involved. Obviously, there is more scope with the regular staff than with the blow-ins. Really, there is no harm in asking for what you want. Don't assume people know what you want, you need to ask.
I am not associated with the shop at all - I just like the place - so I can't speak for them. But, to give you an idea, I get $10 off a half hour session and $20 off a one hour session, with certain workers. Not with all workers, and not when they are busy. Just ask and see what you can get.