Essentially yes, except they make it when you arrive (at least if you pick up in the drive through). This is good design, because food from Taco Bell has an expiration date of about 3 minutes after it's cooked. It's good (well, not good, but it's food) right when it comes out, but once it cools down a bit it becomes essentially inedible.

The craziest thing anyone ever did was reheat a 5-layer beefy burrito.