People always have to deal with anxiety; no matter their power level, social class, or race, at some point, everyone meets such a merciless feeling.
That feeling mostly comes when people are waiting for something to happen or someone to make that thing happen; be that as it may, such desire corrodes their peace and makes every second an agony.
To contain anxiety, people look for different methods, some very peculiar, but it is not the case with eating. Feeding satisfies the body and can give a false sense of relief to the mind as well.
Eating was the way the Mermaid army found to contain the anxiety generated by the uncertain future of their people, the sinister storm that came out of nowhere, and especially Lucien.