WinCo Foods review: Checkout services

Visited my local store for a few items. It was about 9:30 PM (PST). After filling my cart with my grocery items, I went to the self-checkout lines. I was told that I had more than 15 items, and couldn't be in that area. I did have more than 15 items (maybe 20?), but there were only two registers open, both with approximately 25-30 people in each line. I went back to the self-checkout lines to try again. There were 5 checkout registers available, with no one waiting in line, so I politely asked if I could check out there. The person on duty was very rude and said " I can't allow you to checkout here". I asked who could allow me, who's in charge...a manager perhaps? He refused and said he was in charge. I asked him if it was worth losing business? I then gave him my cart and left the store. Antelope has four other grocery stores. Who needs customer service (or lack of) like that?