Continuity mistake: When the government guys come into the store in the evening they arrive, the wall clock shows 8:20, but the head guy's watch shows 6:28.
Suggested correction: I can't remember the last time I went into a house and saw a working clock on the wall. Very simple to explain, they just haven't changed the battery in the clock due to sheer laziness.
Other mistake: If the flying creatures sense heat, then the junkyard should have a lot of heat signatures, but the aerial photograph has none.
Suggested correction: It wasn't an actual, fully operational junk yard with car crushers, cranes etc. It was just an area that the residents had designated a junk yard.