Qr codes

My little sister went to Maponya mall to buy herself lunch using coupons that she won from Vodacom shake and she was told by the teller that they only scan and they don't insert the wi code manually, what surprises me is that other Nandos like the one in Florida scan and they also key in the wi codes manually. I then asked my other sister to go to the same restaurant (Maponya mall) to try the coupons and she was also told that they do not key on the wi codes so my question is what happens if a person doesn't have a smart phone? And why would they send an SMS with the wi codes if people are only required to have smart phones to scan the qr codes at Nandos Maponya Mall branch?