Exactly Zebra' the hoofed animals at this zoo are really lucky as they have big lovely pens, the cats are kept in prisons, like you said with the size of the zoo so many chances are missed to improve.
Sure these can do with some grass for sure, but in gereral the hoofed animals are better served than the big cats.
I don't know the history of the pens for zebra's etc as I only visited this zoo one time, did they ever have grass in the pens in the past and the animals killed it or was it just always sand or whatever is in there?