I have one of those jobs, kinda - read on...
I've always wanted to take my son to the UK because of my heritage. And maybe even the Bristol Zoo because of their attention to biodiversity, threatened species, nature. I saw this about the Bristol Zoo so I browsed around some. Then I hit this article that says the story is an Urban Legend:
Bristol Zoo parking attendant myth | Bristol News | This is Bristol
Bummer, I guess the job doesn't exist. So, in a way, I have the same job (in my mind).....LOL