Factual error: When the TV store is closing at Bloomingdale's, The Richard Simmons Show is shown on the monitors. In 1984, when the film is set, this show was broadcast only in the morning and was not released in syndication. The show would therefore not have been playing on a television channel in New York City in the late evening.
Factual error: When Allen falls into the water after Fat Jack's boat hits him, his wallet falls out of his pocket and rests on a coral reef. The ocean off Cape Cod is much too cold for coral reefs.