Hint: A LOT.
ESPN claims that an average of over $87 was spent per person, meaning a family of four was out almost $350 before tickets, travel, or merchandise (gotta have those jerseys).
What were they buying?
Basic concessions, like a slice of pizza, went for $10 according to the official Super Bowl 50 app, while a glass of wine started at $12. Upgrade to beer for $13, or $15 for a premium beer.
With an average ticket price on the resale market going for $4,500, it's easy to see why a $7 of bottle might make sense to some.