I really dig this movie. Gamera was not the hardface criminal as Godzilla was in his debut. He was a misunderstood kaiju that woke up from an eternal nap and found his world inhabited by humans. A bit groggy in the morning and cranky, he did wrecked the ice ship, but hey, the humans were screaming profanities at him. You might see Gamera destroying Japan in this movie but he's only looking for food, can't teach a kaiju table manners. He eats petroleum which humans produce alot of.
I think the connection with the boy was a hidden message that even though Gamera was big and scary, he is just a child himself that just doesn't know better. And why should he.
As a whole, this is low budget at its finest.