I can't remember the entirety of the Ferdinand Feghoot story about the large, tigerish alien visitor who alarmed the populace by sauntering up to a construction hoarding where people were looking through a knothole at the work in progress, purring loudly, then yanking out the board with the knothole and devouring it.

Turned out it was just a "Purr-Pull Peephole Eater."