I understand your point but football is routinely played on Christmas. Actually, the league does make some allowances.
It depends on the year. For instance, in 2005 Christmas was on a Sunday, but they played the games on a Saturday.
And I vaguely recall that in 2011, Christmas was on a Sunday and they played most or all games the prior day.
Some years they've had a Christmas night game.
But I don't think they do it routinely, at least not any more.
I believe there might be a league rule (or understanding) that from now on, no NFL games from 8 PM EST on Christmas Eve to 5 PM EST Christmas Day.