A while back, people were putting cucumbers next to cats and watching them freak out. The theory was that the sudden appearance of a strange green object caused the cat the panic, thinking the cucumber might be a snake.
So when someone put a foam finger with the Detroit Tigers baseball team logo on it, you might expect a cat to be more reasonable and not freak out, but you’d be wrong. The sudden appearance of this foam finger caused a cat to flip out and flee for its life although its unknown what the cat thought of the foam finger.
Perhaps he foam finger reminded the cat of a snake or a ferocious predator in the same of a hand.