I used to work in a movie theater. I worked a double-shift one Christmas. Business was pretty brisk.
I figure what happens is: people wake up on Christmas morning, open their presents, ooh and aah and play with new stuff for a while. Then there they are, at home, looking at each other, with nothing else to do and nothing good on TV. So they go to the movies, because that’s something to do together, and kind of a “treat” for everyone.
Horse$#!*. Between all of the people who practice one of the religions from the Middle East to the Far East, Muslims, Jews, Hindus, Buddhists, etc., along with atheists, as well as necessary workers, first responders & anyone who cares for sick/injuried/elderly/infirm (hospital & nursing home/assisted living employees) as well as those not celebrating with family there is a decent percentage of this country that is not celebrating anything on Dec 25th.
I hear what you’re saying, but if there just happens to be something I need (batteries, milk, plunger, whatever), I’m probably not going to stay home and suffer on principle.
I’m going to make note of what’s open this year. The last time I checked, it was pretty much just gas stations and pharmacies. I know Taco Bell is closed 
I’m a store cashier who has worked the past 5 Christmas Days. My favorites are the people who coming in when we open because “I have to get a toy before my kid wakes up.” What, you got no advance notice that December 25th is Christmas?
Some people do say “You shouldn’t have to work today,” but we get much more “Thank you for being open today.”