so I can grip and let the fish in water while preparing camera/scale.
That's most of the reason I carry one considering the fact that I don't use lures with treble hooks.
Of course the large barbs on catfish can inflict some serious pain making the jaw grip especially useful.

(Caught a carp that size from my canoe and it towed me upriver as if it wasn't even hooked. Talk about a really dumb fish.....)