Clicks Pathetic Policy

I purchased some reading glasses yesterday from Click Townsquare, but took them back today as they were not suitable. I did not have the invoice with me as I have Clicks Card. They refused to refund me without the slip, and would only consider an exchange. I cannot understand this as most other retailers where I have a card (Dischem, Makro etc) just look up the invoice on their system using the my card to access it. Are Clicks so behind and out of date? Its pathetic, and I will avoid using them going forward.