I get annoyed by it too, they have been overlooked for far too long, but it's not just smaller cats, big cats too face the same poor deal, bears are also in a similar position in some places.
It's one of the worst exhibits at Cotswold as the enclosure doesn't suit the species (to my way of thinking). Pallas' cats are rarely shown well in the UK, and they generally deserve much better accommodation, although they seem to do well enough.