Misleading customers at Markhams

I visited Markhams this morning at Woodlands Mall Pretoria East. When i took all my clothing items to the paypoint, i was asked for my cellphone number. I declined to give it as i was paying cash. I was told that if i do not give my cell number that i do not qualify for discounted items, even if the discount is for the general public and not account holders only. I left everything on the counter and walked out. I have been a loyal customer since Markhams opened in S.A but not anymore. I will never shop there again.