John Lithgow was born in Rochester, NY, where most of the movie was filmed.
When showing his shelter for the first time there are 3 jars of Vegemite. This is an Australian yeast extract spread (like the UK's Marmite) much loved by some in Australia, but an acquired taste. It does have a very long shelf life and a little goes a long way, so could be a favourite of 'preppers'.
At Thanksgiving dinner the Twilight Zone is mentioned in conversation/argument. John Lithgow starred in a segment of 1983's "Twilight Zone: The Movie".