Sketch portrait by  bugmemory

When you live in a world with a wide range of species and body shapes, sartorial preferences vary greatly. Emmet's casual look involves t-shirts and blue jeans, while Sully prefers a more old fashioned working class aesthetic. Nobody bats an eye at either.

(He didn't wear the red kerchief before he started working at Emmet's burrow, where he copied it from him. He seems to view it as a "badge of office" of sorts. To Emmet it's just a rag.)