I think people keep forgetting, when you go to a z...

I think people keep forgetting, when you go to a zoo, is not for any of the animal to entertain you, is YOU who were visiting their living area so don't complaint about what the animal didn't do for you. When they didn't come to the door to greet you? Don't cry.
As for the ticket, strongly recommend "Full Experience" ticket and buy it online before you got there. All and all, excellent experience and would strongly recommend this place.