A croc is doing what it does naturally. The croc saw prey. The croc must eat, it's not going to say "It's evil to eat a human". It's unfortunate, but it's the natural way of things. No animal is worthless. And no animal is "good" or "evil" as defined by humans.
no -when the croc saw the kid he saw an opportunity to scare and torture
There was plenty for the croc to eat instead of a human-more than likely it wasn't even that hungry but just wanted to cause terror
There are plenty of worthless species
Every bee except gentle bumble and honey bees
Venomous spiders and snakes
Those worthless killer lizards on the island
They are worthless and quite evil
No one ever will say thank god for brown recluse spiders they keep the ecosystem running