Patehtic service to swop items

What pathetic service! My son bought me a pair of rynning shoes a week ago but the shoe was a little tight so i went to Greenstone branch today to swop it. Firstly they lady behind the till scanned my returned item and said that it was now on special. My son paid full price for them and the price was on the original box. They would not give me the full value of the swop. I did not want a refund. Only to swop for another pair. Then after an adement NO fron the sales person...I paidnin the difference only to find that she wouldnt guve me a slip for my new purchase!!! She said sorry it was a return and repurchase. I have never in my life dealt with a shop that has such a pathetic return policy. Mr Price.... this is realy bad serv9ce from your company. Very sad....