Interesting! Which part(s) of the US do not mean this literally? What does it mean in that context?
In other parts (the south, but I'm not sure where, maybe North Carolina?) it is an expression that just means nice to see you.
Note because it is an expression in some parts you hear it often from those people. People from the other parts don't invite people over often so they rarely say it. Thus the impression that it is universally used, when it is only a small region that says it often.