Kristin Lee versus the Alternate Universe Tim Guy

Whatever happened to "the customer is always right" or, at the very least, confirming that the customer is wrong? This morning I drove by the Tim Horton's/ Shell Station on Killingly Street and the sign advertised Tanks (the extra large, served in a lovely styrofoam cup) for $1.09. Tanks are usually $1.90, so this was apparently an accident, but Tim Horton's is still obligated to sell the Tank for $1.09 as advertised.

Me: So, your Tanks are on sale, eh? (Note how I was trying to be nice. I could have come right out and said, "Someone fucked up your sign.")
Tim Guy: Uh, no, they're the usual price.
Me: Well, your sign out there says $1.09.
Tim Guy: What sign? (There was only one sign, and I pointed to it.)
Tim Guy: Oh. It doesn't say $1.09. It says $1.99. That's the usual price. (It wasn't.)
Me: I checked it twice.
Time Guy: The other 9 must have blown off.
Me: No. There are three digits. One. Point. Zero. Nine.
Tim Guy: I put up the sign this morning and it said $1.99.
Me: That's not what it says now. (As the guy obviously had poor comprehension skills, I gave in and bought Dan and I each a medium coffee instead.)
Me: Any idea what "Happy People W Antedam" means?"
Tim Guy: What?
Me: That's what the other side of the sign says.
Tim Guy: Well you see, the numbers blow off. (This, to him, was sufficient proof that he had won the Tank argument.)

I surrendered, and sat down to scratch a Crossword ticket with Dan. Mark my words, if that mistaken sign is still there tomorrow, I will be merciless, and I will have my ultra-cheap Tank.