>>At the end of the day.
>
>...we'll call it a day. But what have we called it before?

Not sure you'd get this one, as maybe it's more of an anglecism. It's used far too often and frequently as an adjunct to "but" or to mean the outcome of something,

e.g. "They may scream and make a nuisance but, at the end of the day, they're my children" doesn't mean they're someone else's during the afternoon.

Another e.g. "They fought the enemy for years but, at the end of the day, they won"

e.g. "Milan were way ahead but, at the end of the day, Liverpool won"

What a useless, mindless expression.