Bcuz it is technically not worth ur money since they close at 5pm. They don't wanna charge u full price and they don't have a cheaper price for that time yet.
The 1st 2 answers nailed it, but let me just address the statement in the question "They should work more than 5 hours" 😳 first of all we were not put on this planet to work 9:00 to 5:00 Monday through Friday on a fixed schedule made of imaginary time created by psychos who also created money and taxes. Maybe the animals don't want to be disturbed by humans 24/7 because they're supposed to be out in the wild and not in cages. They are not there for your entertainment and who cares what the reasoning is that they only work for 5 hours. We're not all here to be robot slaves who were put here to serve others at all times. And thery are certainly not going to work to make sure people like you get to pay to walk around for an hour for your exercise plan or leisure. Seriously? Get over yourself in fact start working for yourself and maybe then you'll understand how much your statement makes you sound like you've been brainwashed by the system. Stop and smell the roses and find better to do.
Because it takes more that 2 hrs to go through the hole place.
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