Where do you live that you can get a "nice" entrée for $13? That's what McDonalds costs here...
$13 gets you a nice entree in most any US city. Not white table cloth service of course, but you can find good and healthy food. Especially if we are talking just about the entree.
I usually don't spend less than $15-20 at fast food. But often it's multiple burgers without a bun, and a couple of side salads.