All machinery needs power: typical prosthetic limbs run on internal batteries, or utilize glucose converters to siphon blood sugar. While her own have been modified to do the same, the ColdShoulder standard is meant for use on robots connected to a power supply or with massive battery packs, not mounted to a living body. Keeping all four arms and the assorted other components running as constantly as the head moof prefers requires considerable amounts of supplemental energy.
As a result, Balina has a significantly higher caloric intake than her species or build would normally require. The converters only care about glucose and electrolytes, so she has a strong preference for inexpensive, sugary treats with little other nutritional value. The fact that this means consuming an inordinate amount of junk food on a daily basis is simply a happy side-effect.
This was supposed to be an article poking fun at the head moof's eating habits. I think I lost the thread somewhere. "Hahaha, look at that," I said to myself, cracking my knuckles and typing, "She needs to eat more, but she does it by consuming sugary treats instead of anything remotely healthy. This is amusing to me."
At which point, Ms Mahigan tapped my mind on the shoulder and said, "You realize that they just run on glucose, right? I don't need extra vitamins or anything, so buying a bunch of vegetables or meat would simply waste money and be a fraction as fun. Maybe some electrolytes would help, too, but hey guess what else has huge amounts of sodium in it?"
"Fuck," I said, admitting defeat, "I guess I thought this through without telling me first, didn't I?"