When I am in the checkout line paying the cashier, or paying a bill in a restaurant, or finalizing any other countless interactions that could occur at any time in life, I like to say “See you next time!” instead of pretty much anything else. It is simple but forward thinking and positive.
In my opinion, “See you next time!” creates the thought of a positive future. We know that looking forward to things can be beneficial and healthy when used in the proper context. “See you next time!” is no different.
Whether I am in at a small super awesome café on the beach in San Francisco or an airport bar in Tokyo or where I may never return and the likelihood of seeing that person again is virtually zero… I still like to say “See you next time!”
After all you never know when your path will with anyone else. All we know is the universe is unfolding as it should.