[dendrite9]

I think Yellowstone is too big for that compared to places like Zion and Yosemite which have relatively small valleys where people concentrate. I'm not sure shuttles to see Tioga Pass would make sense in the same way they do in the valley.

[marssaxman]

There is in fact a high country shuttle operating in the Tuolomne Meadows area. It makes four stops per day at Tioga Pass:

https://www.nps.gov/yose/planyourvisit/tmbus.htm