I'm reading about the Shuttle System in Zion. As far as I understand, there are two types of shuttles. The first one gets you from Springdale to Zion Park Fee Collection Office, and the second operates within the Zion Park. Cars are not allowed to enter the park when the shuttle is operating (correct me if I'm wrong * [see an addition below]).
The fees page mentions the $20 per person entrance fee. And it doesn't mention anything about America the Beautiful Pass. If a group of 5 people is travelling in one car (and is normally admitted to national parks without additional fees), are they required to pay $20*5 additionally to enter Zion (since they will not be entering Zion in one car)?
* Even if my understanding is incorrect and the cars are allowed to enter the territory of Zion, the parking near the visitor center is known to be always filled up, in which case, I assume, the only option is to park in Springdale and take the shuttle to Zion Park Fee Collection Office.