Rude owner bad bad service

I went expresso as usual for my black coffee however this morning I bought a mug as advertised the assistant brought me a dirty mug I ask her to clean it as I want that color and it was on one left in that color lo and behold I waited for my coffee after a few minutes customers is complaining about the lady who serving and making the coffee or what they ordered I didn't take note cos I'm waiting for my turn. When it was my turn I politely told the lady I ordered black coffee cos I'm allergic to milk fine she threw the coffee out and processed my order to my surprise the mug was dirty again I ask the lady to clean the cup please she nearly bit my head of screaming I ask why she screaming I was not rude I just pointed out the cup is dirty now she screaming even louder I ask to speak to the manager I was told she is the owner and if I'm not satisfied I can get a refund wow Il never buy from that store again if that was the reaction of the owner to customers who only ask to clean the cup