I really wish I was kidding

Hi everyone. First time poster here! -wave-

I think this classifies more as a WTF that anything. Though, a little info that's pertinent to the story. I'm left handed and I'm use to people coming up to me and being oh-so-amazed that I'm a lefty. Which annoys me, but I deal with it. But yesterday's (as it is already 2 AM) event really took the whole cake.

I went to the grocery store to get a few things. I'm checking out and my cashier is an older woman. She seems nice and all, making small talk as she's ringing my items up. After she tells me the total I hand her my card. From here we'll go to script form for entertainment value.

Me: -headdesk-
CL: Crazy Lady!

Me: -signing slip-
CL: Do you worship Satan?
Me: O.O Uh...no. Why?
CL: Because you're left handed. Left handed people are EVIL!
Me: Wait. What? Ma'am you really need to get your facts straight. Left handed people are not evil.
CL: NO!It's true! The latin word for left is sinister!
Me: Wow. Just...wow. -quickly gathering bags-
CL: You need Jesus! -yelling this as I'm hurrying out the door-

I really really REALLY wish I was kidding.

Thoughts? Should I call the manager and speak with them about this? Or should I just let it go?