Avocado Spread

I went and picked up a sandwich at lunch the other day and the menu said it had "avocado spread."

Me: "What's the avocado spread?"

Sandwich Girl: "Well, the avocado is a green thing--I don't know if it's a vegetable or a fruit--"

Me: "Uh, I know what an avocado is, I just wanted to know what's in the spread."

Sandwich Girl: "Avocados."

Me: "But it says it's a spread"

Sandwich Girl: "Right."

Me: "So how is it a spread?"

Sandwich Girl: "We spread the avocado on the bread."

I just want to know, at what point did I become the idiot in that conversation?