My experience has been odd. I have stopped in the shop at least twice and more likely three times, each time asking to be notified by email when there is a sale on my favorite bra, the Never Say Never Prettie Underwire.
Each time I have dutifully given my name and email and anything else the sales person asked. Each time I have been assured I will be notified when the next sale is imminent.
I have never -- years have passed in this process -- been notified. It is possible, I suppose, that the store has not had any sales but that seems unlikely to me.