They've Got To Tell You

Pretty strange that in a 1982 movie they'd have a prop poster up of the Super Bowl (SUPERB OWL) XXII. This superbowl took place on January 31st, 1988, six years AFTER the release of Poltergeist… the very same day that franchise star Heather O’Rourke fell "ill".
Coincidence?
How many coincidences before it's mathematically impossible?