Innocent Until Proven Guilty

Friday evening I had an intense session with the trainer before heading off to practice more for the "tap-dancing nuns" number. Fresh out of water, I decided to fill up my Super Big Gulp cup at the closest 7-11. I asked the cashiers if there would be a charge for the water, knowing that they never charge for filling your own cup with water, but wanting to be honest just in case policy has changed. They, of course, said no but that there would be a charge for the cup. The following conversation ensued:

Me: "I brought this cup in with me."
Man 1: "I didn't see you bring in the cup."
Me: "Are you serious?" (I really thought they were joking)
Man 2: "I didn't see you bring it in either."
Me: "Are you kidding me?"
Man 1 & 2: "No, you didn't bring that cup in."
Me: "Ok, well look - here is the dent from where the cup has been sitting in my car and I can show you the puddle outside of my car from where I dumped out the warm water to refill it with cold."
Man 1 & 2: "Well next time you need to show us the cup, but we still don't think you brought that cup in here with you."
Me: "So, do you want me to pay you then?"

You can tell when someone does and doesn't believe you and they most definitely think I am a thief.
Naturally, the next day, I stopped by the same 7-11 on my way to rehearsal. Man 1 was working with a line of 5 or 6 people at the register, but I SHOUTED as I entered, "I'm bringing in a refill cup!" As I walked out, not even waiting in the line, I just shouted, "I just filled it up with water!" He nodded and said, "Thank you."
The lesson I learned? The people at 7-11 like annoying, loud people more than honest, quiet people. I just wanted a super big gulp of water!