"Safe," Xel says coolly, "and out of your reach." And it is, indeed, not visible. "So, if you would like it back..."
He stoops gracefully and takes two gentle fistfulls of Rincewind's shirt, smiling dispassionately. "Listen very carefully, please. I don't care if you make a mockery of the service profession, because, as I'm sure you have realized," his eyes open just long enough to scrape, or perhaps scour, up and down Rincewind's form, "people like a clown, provided he isn't wearing makeup. But you are going to learn to take a fall without dropping or breaking things, do you understand. Now, I'm not going to make you go out there without your hat now. This is in the nature of a warning.
"You will not leave when the pub closes; you will remain behind for your first lesson. And you will be very, very careful for the rest of today, won't you, because if there is another clatter, crash, or splatter from you, you will find this hat on your head again for a time, and look around you, please." He waits until Rincewind's gaze has flinched over the prep cooks, turns his voice very, very soft, so only Rincewind can hear him. "Do you think you can rely on these people to make it easy for you? Not to trip you or give you a shove? I think, in your place, I wouldn't count on that, you know. So," he switches the hats back, hands moving too quickly to follow, "you probably want to be a little more careful. Because," he flashes Rincewind a white, humorless smile, "I can find that hat of yours any time and anywhere I like, now. So if you're thinking about running away," the smile widens, "keep thinking. I haven't had a good hunt in far too long."