Refused over the counter medication

I was doing some shopping about two days ago at the checkers hyper in Sandown centre Parklands. As I needed to get to a pharmacy I found it convenient to make use of the pharmacy inside checkers as I was already there. I got the the pharmacy counter and request a bottle of cough syrup which does not require a prescription. The woman that was serving me immediately refused to supply me the medication and said I needed a prescription. I asked why that is and she told me that there were reports of abuse of that particular brand and seemed to have a very bad attitude. She then stared at me blankly. First of all even IF this was the policy there was absolutely no clear signage that this was the procedure. Even if there was, this woman did not even offer me an alternative that was not prohibited. I felt as if she was implying that I was an addict or something judging by her attitude. I felt discriminated against and left feeling very embarrassed. This was the first time I had been to this particular pharmacy and will be the last. I then left and went to one of their competitors and they helped me gladly and did not make me feel like a ********. How disgusting and rude!