They do, this pic just shows the grassy/shade area of the exhibit, which is only about 1/4 of the exhibit. The exhibit also has some more rocky areas, a stream, and some more grassy areas.
I love this exhibit, and think it is very nice for Snow Leopards. When I saw this exhibit in person (November 2007), the two cubs were running and jumping all over the place. They were also given pumpkins and they were rolling them around and it was really fun to watch.
The cubs are now gone, but now that is getting cold again even the adults are being playful. Last week the two adults were acting as though they were the cubs. I'll post some pics of the leopards later on.