Unsoilicited sms's reacting to private data about my purchases: uncalled for and unprofessional

Let me state it upfront: I am a longstanding customer of Dischem, and a grateful one at my branch for more than a decade. I like what they offer and their swift service. Here is the BUT: Out of the blue data the company are clearly gleaning from my orders (chronic, scripts, etc, apart from other purchases whether OTC or from the isles) are now being used to make all kind of suggestions to me with url's embedded to inform or train or coach me into buying habits or considering it. This is breach of privacy. The worst is that the torrent of sms's that I am being bombarded with without request or permission, contains the supposedly option to respond with STOP - several responses later, the unsolicited, unwanted, uncalled for, sms's transgressing on privacy and using private data without consent just continues to arrive. Unacceptable. Both issues.