Okay, so we know Seuss was a fan of the work/life balance. But The King's Stilts seems to be stressing another kind of balance, too—an ecological one.
Wait. What? No, seriously. Hear us out.
We're talking about the Patrol Cats and Nizzards. They're archenemies, sure, but they're both equally important when it comes to the ecological survival of Binn. If the cats are working, the Nizzards are flying off. If the cats are lazy, the Nizzards are wreaking havoc… after all, while the cat's away, the Nizzards will play.
So we get a rather dramatic standoff between the two:
A hundred thousand Nizzards stopped their pecking and sprang to meet the charge. The Dike Trees shook as the cats roared their warcry. The sea's surface swirled into wild raging whirlpools. (114)
Talk about intense. But much-needed, nevertheless. Without this battle, balance could never be restored (which brings us back to Seuss's whole we should intervene in World War II argument). Afterwards, the cats and Nizzards simply go back to their usual roles, keeping the Kingdom of Binn in perfect, if somewhat precarious, harmony.
See, if you throw the Dike Trees into the mix, you'll realize that none of these species wants to eradicate the other, but they need to be kept in check in order to coexist. The Dike Trees are necessary to keep the sea out, the Nizzards are necessary to keep the Dike Trees from overgrowth, and the cats are necessary in order to keep the population of Nizzards from eating away at the Dike Trees until they are destroyed. If this balance weren't here, the cats would just sleep and the Nizzards would eat themselves sick. And Binn would, well, drown.
Though it may seem that the cats are out to get the Nizzards, you'll notice that the cats don't destroy and kill them all with wild abandon. Instead, they just want to keep them from eating at the Dike Trees and threatening their dry land. The antagonism isn't what's important; the natural balance is the critical issue. These species keep each other in check.