Castiel answers by silently pushes his cup closer to the teapot.

They've little to say for the remainder of the meal, but that's all right. The silence manages to be companionable. They finish and depart silently and in the blink of an eye, leaving the waitress to look rather puzzled as to where her two customers went.

But not nearly as puzzled as she looks when she goes to clear the table and sees what she's been left as a tip.