The sign is a subtle joke. The shop is called "Sneed's Feed & Seed", where "feed" and "seed" both end in the sound "-eed", thus rhyming with the name of the owner, Sneed. The sign says that the shop was "Formerly Chuck's", implying that the two words beginning with "F" and "S" would have ended with "-uck", rhyming with "Chuck". So, when Chuck owned the shop, it would have been called "Chuck's Feeduck and Seeduck".
Gimme gimme chicken tendies, be they crispy or from Wendys. Spend my hard-earned good-boy points, on Kid's Meal ball pit burger joints. Mummy lifts me to the car, to find me tendies near and far. Enjoy my tasty tendie treats, in comfy big boy booster seats.