At one time Benny mentions a "Duce" who got hit by a train. This is a reference to "El Duce", lead-singer of punk-Hardcore band "the Mentors", who claimed Courtney Love offered him $50,000 to kill Kurt Cobain. He appeared in Nick Broomfield's "Kurt and Courtney" documentary. He died under misterious circumstances after he made these claims.
Blue Ruin is the colour of Kate Winslets characters hair in 'Eternal Sunshine of the Spotless Mind'. She mentions it soon after they first meet on the train.
When the main character returns some empty cans for money we see several cans returned. But the deposit ticket (briefly) only states 20 cents. It won't be enough for most purchases, let alone the map he buys in the next scene.
When Dwight stops at the diner to inspect the parked cars, he tests the handle of the Chevrolet truck. The door is supposed to be locked, he goes on to bust the window out. However, when he tests the handle, the door opens a little bit, thus revealing that it wasn't locked in the first place.