How to Deal with Endings

Typically, things end with a period (.) Grammar is so easy to construct an ending, a goodbye. All you need is a simple (.) or (!) and you're golden.
Ending a conversation is slightly more difficult. In American culture, you greet a person by saying, "Hey, how are you?" and then walk off without a response, because we have an unspoken agreement with people that our 'hellos' are also our 'goodbyes.' Similar to the Hawaiian 'aloha'.
But leaving a place, knowing you will most likely never see some faces again, what do you do?

My plan: Shout "period!" and "exclamation mark!" whenever you leave someone you will probably never see again. Even though they may have no clue why you suddenly got grammatical terrets, they will always remember you as the person who shouted nonsense right before leaving. And maybe they'll smile. And wonder who the hell was that kid?!