Builders Express turns pensioner away

Yesterday I made inquiries to purchase an Inverter / Generator from the store for my Dad, being a pensioner, I spoke to the manager of the department and asked him for information regarding the pensioners discount, they informed me that I should bring the pensioner with, I asked cant I just bring the id booklet instead of having to take my dad all the way to the store. I was informed to bring my Dad along, I drove all the way the fetch my Dad which is about 10 km in one direction. on my arrival back at the store the sales person helped us when we got to the till point. My Dad did not have his Id with him, even though I was told to bring him to the store. We were turned away and they insisted to see the Id at that time it was peak hour traffic we were never going to make it back before 6 pm never mind the driving up and down and after making the inquiry first time around. We could have been granted the opportunity to pay and then bring the proof of Id later. Also had the manger that I spoke to made it clear that they were going to require the Id we would have brought the Id with? What a waste of time and inconsideration to your customers