In a car moving forward, he would not smell the coffee brewing in the trailer that he is towing.
When Donovan crashes the bus in the latter part of the story, Casey and one of his thugs get on the bus and all the passengers are gone, even though there was no way for them to get out in such a short span of time.
When Jerry and Pete get up from eating their ice cream after seeing the bus, studio equipment is seen reflected on the side of the shiny black car.