In retail, in CA, mileage is commonplace for all floaters if traveling over 30 miles - not if you have a regular location which is over 30 miles (ie - it was your choice to take the job so you accept the travel).
If you attend a required meeting or training which takes place over 30 miles away from your home store (not your home), you can take mileage.
I've never heard of a company car - even the RPM doesn't use a company car - he gets mileage though (what an awful job!!!).
In hospital work, I don't know of any place that pays for mileage. We use our own relief staff to cover vacations, but years & years ago when we used agency staff, the hospital just paid the agency. I don't know what the actual pharmacist got paid from the agency (time plus travel or just time).