Bad customer service!!!

This morning at about 7h05 I was at the Freshstop @ Caltex in Montague Gardens. I bought a flavoured water and asked the cashier what coin does the toilets use as I needed to use their toilet and the toilet had a coin-lock in place. The cashier told me in so many words that the toilet is locked and they're not going to open it, because they say it isn't a public toilet. Now, that I understood if someone from the street came and wanted to use their toilet... BUT me, I was a customer of theirs!!! I then told the cashier that is terrible and I won't be going to them again.