****ty exchange policy

How does such a big company carry on with a ****ty policy. I brought items the sizes are wrong I want to exchange I'm told I need a slip. Customer relations says if u purchase an items and it's still in the right condition and price tag you may exchange. So truworths seems to think they above the law. If other companies can work on that policy why can they not. Sooo many complaints about the above situation and no change. No respect for they clients