In terms of eating options around the Grand Canyon, your choices are pretty limited. Inside the Park, you can eat at the El Tovar Lodge, but you have to be in the mood for an over-priced sit down meal to enjoy it. There are also two cafeteries in the Park at Maswik and Yavapai Lodges where you can enjoy institutionalized classics like dry Salisbury Steak, overcooked Spaghetti and Tomato Sauce, watery Chicken Pot Pies, and the Mystery Meat special of the day. You're really better off picking up something in Tusayan or Williams, AZ and bringing it with you into the park.
After my day of hiking the Canyon, I was famished. I stopped by Wendy's in Tusayan. For some reason, Wendy's is always exotic to me. Maybe because the first time I went to Wendy's was when I was in my 20s. We had one or two growing up in Virginia, but they were located in the most inconvenient places, not close to any easy turns. And right now I don't live near any here in New York. This one in Tusayan was also extra exotic because it was all run by Native Americans, not that this Wendy's was in a teepee or anything.
At any rate, I got my dinner, and sat down to eat. A couple came soon after and sat at a table near me. The wife asked the husband what he wanted:
Wife: So what do you want?
Husband (not really paying attention): Oh. I guess, Nachos.
Wife: Nachos????? They don't have Nachos here. Hmmpf.
I wish I could have captured the wife's LOOK of indignation and scoff. It was a look that simultaneously made her husband feel like he was 5, and demonstrated her clear expertise in Wendy's menu.
To the husband's credit, I do think Wendy's had a Mexican burger at some point. Of course that might mean it's just a regular burger made by a Mexican.