Walk up to cafe counter...
"What can I get you?"
How about a coffee?
"What size?"
*I smile* How about any size that comes in a mug!?
"Here you go!" *she hands me a mug and I go to hand her my credit card*
"You're fine. Don't worry about it."
*I pause briefly before deciding it is probably in my best interest to act naturally — so I smile, say "Thank you!" —
— and walk away determined that the only logical explanation is that I am an X-man with an unknown super power — a power which I am now determined to master.
MUAHAHAHA!