Fuller Thomas: Do what I do. Just remind yourself that in a hundred years you're gonna be dead. It's the closest thing I've got to a philosophy.
Venna: I'm not going anywhere until somebody tells me why I should be afraid of a radio.
Fuller Thomas: Do a woman's voice.
Fuller Thomas: Hey, you came all the way to Salt Lake for me?
Lewis Thomas: Well, you are technically still my brother.
Fuller Thomas: Come on, I know what Dad says about me behind my back. That I'm the world's biggest loser. And that's coming from a plumber! That's coming from a man who wears a lime green jumpsuit to work everyday.
Lewis Thomas: You should call home every once in a while. You know, when you don't need bail money?
Fuller Thomas: Yeah, but how often is that?
Rusty Nail: I was just playing.
Answer: For Fuller and Lewis, the best assumption is that he never actually left the first motel. He stayed at or near the motel, followed them to the police station, and then continued following them up untill the point where he makes his presence to them known again. Or he also could have just parked his rig somewhere far down the road and waited for their car to pass him, and at which point he would start following them. And for Charlotte, he probably just followed Fuller and Lewis all the way to the college, saw Charlotte, and then kidnapped her while she was leaving.