Wanda has a passion for processed foods. Red Vines, Snickers, and Pop-Tarts: they're all "delicacies" (18.56). That's not a term we'd ever use for a Pop-Tart (a toaster strudel, maybe) but remember that Wanda hasn't seen delicious junk on any of the previous eight planets she's been on. She values it more than actual food, as we see when she finds a delicious cache of junk food: "I was surrounded by food. Not just rough bread and weak onion soup, but food. [...] Chocolate chip cookies. Potato chips. Cheetos." (27.16) You know, stuff you can live off of.
However, the crown jewel of junk food to Wanda is the illustrious Cheeto. Cheetos have never sounded this good. Wanda drools and licks her lips to nearly erotic imagery of Cheetos on two occasions. The first time is when she's trapped in her prison cave, and Jared is withholding Cheetos from her: "The rich smell of fake powdered cheese rolled through my cave... delicious, irresistible. [Jared] ate one slowly, letting me hear each distinct crunch" (18.58).
Later, Ian feeds Wanda a Cheeto: ""I listened to a sharp crackle and a ripping sound... and then I could smell, and I understood. "'Cheetos!' I cried. 'Really? For me?' Something touched my lip, and I crunched into the delicacy he offered. 'I've been dreaming about this.' I sighed as I chewed." (35.58-35.61) That's more romantic than Patrick Swayze and Demi Moore making pottery. We're surprised Wanda doesn't have a sexy pin-up poster of Chester Cheetah on her cave wall.
In fact, when Wanda plans on dying to save Melanie, she wants one of her last meals to be fast food: "I'd just wanted some of the flavors I particularly remembered, one more time" (53.98). By this point, Wanda's grown accustomed to Earth, and she wants to savor this unique flavors, no matter how greasy and fattening, one more time before she can never taste them again. They remind her of her new home, and her life as a human.
But we think Cheetos have more to symbolize. (Really.) They're fattening, diabetes-causing, and have about as much relationship to real cheese as a your pet goldfish has to Jaws. But they're delicious—just like Earth. We may not be able to do everything right. We may be mean, argumentative, controlling, and frankly a little destructive. But there's also love, companionship, and mercy.