I bought two packs of cat food at HK$119 each but was charged $143 each (about 15% difference!). I didn't notice the price difference until I got home. I then went back to the store but the salesperson refused to return the difference to me.
I filed a complaint to the Consumers Council. More than a month after the Council written an enquiry letter to the store, there was still no reply. After repeatedly asking for a reply, the store owner finally asked me t0 visit the store again to get the money back, and he refused to send the money to my home address.
I felt like I was totally humiliated by this pet food store.