No way to stop annoying SMS marketing

5 Times I have opted out of Woolworths Holiday deals by doing what they suggest in their SMS, by replying NOSMS. And still it pesters me. Overall I cannot stand Woolworths pricing structure. After discounts their prices are still higher and it is not that their products are always fresher or better - myth. And to top it all I then phoned customer service: "we experience high traffic, please wait for the next available agent..." And then the line drops. Every time.