I can see there are people out there who have never ordered, say, chili in Burger King or a chicken leg at Long John Silver, just out of, say, “absent-mindedness”. Once, the poor kid looked twice for the chili key, then called his manager over to show him how to key in chili. The manager was succinct: “Cut it out.”
I used to have the system beat at Chick-fil-a. My order was a 2-sandwich meal, double fries(instead of one fry and one cole slaw) and no pickles. The in-store code for this was, “Double Double Fry No Pick”. Then, I could order my meal using the code, and got my food, correctly, with a smile, usually. I suspect this is the reason behind numbered meals. This gives you the option of saying something quick and easy like, “#4, coke”.
I guess you have to make a value judgment such as this: “Do I want to bend the order taker to my will, or have my food correctly with a minimum of fuss and bullshit in a timely manner?” These people are not working at McD or BK because there were no vacancies for their masters-level education. Adapt and save it for when it really counts somewhere else.