many of these types of games are in fact rigged. They can vary the claw strength so that sometimes it'll never actually grab, and sometimes it'll slip off. And some times, it’ll hold and grab and give a prize. The randomness can be set by the owner,
given that the "big" prize is a cat, I'd just poke the cat until it got out. Maybe they won't know you're the one doing the poking and come home with you.