Do these people need to learn manners?

I was walking and there's this guy that asked me, "Is there a restroom down there?" and I looked where he was looking at and I said "yeah". When I was at work and I was helping out, getting a drink for a customer, I accidentally got him the wrong drink. I was sitting down and he said, "Did I not say Coke?". I think these people need to learn manners, because they are rude. I might be either right or wrong, but I think they should have said, "Excuse me, are the restrooms down there?" and "I'm sorry, but I asked for a Coke". Am I right or wrong? Please help me. Thanks!

100 percent correct....its plain arrogance really