Now I imagine that you, native English speaker, have no clue what I'm talking about. Let me explain myself. For the longest time I've had this fear of places like Subway or Chipotle for one simple reason: too many choices. Yes, they do have a menu, but it's being disregarded most of the time, allowing you to "build" your own sandwich, burrito, bowl. I've come to appreciate this opportunity with time, but I still remember the days I was terrified I'd be asked a question and would have no idea what I was expected to answer.
Imagine not knowing the difference between the choices, and being confused just by most names. Now think about the line of people standing in front and behind you (and feeling like they are all staring at you right this moment and silently laughing at you guessing which planet you came from). And here you are, required to give the answers to the questions you're not even sure you heard right. Humiliating and terrifying, all at the same time.
Corn or flour?
Black or pinto?
White or brown rice?
Grilled or fried?
Mild, medium or hot?
What kind of bread?
How would you like your burger/steak cooked?
What kind of pasta would you like?
That's why I'll always love the good old McDonald's where the ordering process is easy as "Hello, number 3 please" :)