I have a gluten allergy and eat vegan. I knew there wouldn't be many options for me which is fine and understandable. I ended up asking for rice, potatoes and veggies at the grill stand. Chef was a bit confused but complied, but the cashier first asked "no meat?" Then when I said no and tried to explain I'm a bit difficult because of some dietary needs, he shook his head frustratingly and charged me 4800 ISK. I later found out my brother ordered the exact same thing but with meat and was charged 4100 ISK. Never was I rude or made my order anyone's problem. I had no issue paying full price for my plate, but being charged extra and being met with that reaction was unnecessary and rude.