A creation myth that casts humanity as the gods' labour force is not idle poetry in a society organised, at the institutional level, around exactly that relationship. The Mesopotamian temple functioned economically as the god's household: it owned land, herds and workshops, employed dependents, and above all received and prepared food, drink, clothing and incense that priests presented to the divine statue on a fixed daily schedule, the akitu and other festivals simply expanding the same logic to a civic scale. The theological claim that humans exist to feed and house the gods was, in the temple's daily operation, a literal job description rather than a metaphor, and the vast archives of ration lists and offering texts that survive from Mesopotamian temple archives are the paperwork of that arrangement.
The doctrine also shaped how Mesopotamians understood disaster. The same Atrahasis Epic that explains humanity's creation goes on to describe the gods growing irritated at human noise and repeatedly trying to reduce the population through plague, famine and finally a great flood, only relenting when the flood threatens to leave no one to provide offerings at all: a divine realization that humanity's service was, in the end, indispensable to the gods themselves. Read together, the creation and flood narratives present a religious anthropology in which humans are neither central to the cosmos nor incidental to it, but structurally necessary to a working relationship the gods depend on as much as humans do, however little say humanity itself was ever given in the arrangement.