By 
In the beginning, God created the Recruit. He was wretched, diseased and malformed. Cursed to a life of misery aboard the Marine Corps Recruit Depots of San Diego and Parris Island. Part of their torture was being given the opportunity to gaze upon the glory of the soft-serve ice cream machines endemic to every chow hall…but they were forbidden from touching it.
For real though, why is this thing even there? The Marines eat in a separate area from the diseased recruits, so obviously they could remove it from the recruit side.
My personal theory is that it is there just as the forbidden fruit was placed in the garden of Eden: temptation. The Drill Instructors want you to fail so that they have another reason to yell at you.
Don’t be the one that listens to the snake. Avoid the ice cream.
Air Force basic training had the same temptation, but ALSO there was a cereal machine in the mornings.
It was a few weeks in when I learned the dark magics of these things: you could have it, but you didn’t have time to have it unless you were on KP. KP was the most glorious feasting you could get, free of the Snake Pit, as they had yet to settle at their unhallowed table observant of all the beaten down trainees.
And then, just to screw with us, they had Sloppy Joes for lunch during the week we had to wear our service blues.
I remember during Army BCT we had it in stages. Could only have fruit juice, milk and water during red phase. Then we could have sodas in white phase. Then coffee in blue phase. Was the soda good? Hell no. But that coffee. Six weeks without turns it into the nectar of gods.