Rude Staff Member

On numerous occasions this one staff member gave me bad attitude. I always let it slide but today it really got to me. This morning it happened again. He was utterly disrespectful towards me. I cant talk to him without him having to shout at me. Who does that? Who shouts/ argues and exchange words with customers? I've never seen him with a name badge & I believe that's not allowed. After this morning's argument, I decided to ask him for his name, he shouted at me again asking me why I didn't know it, I then told him its impossible to know if he doesn't wear a badge. He then told me that he was Walter, I don't know if that's his real name.