The One Where I'm Offensive to the Cashier

The other day, I was buying shitloads of candy for my kids for our Annual Egg Hunt and Candy-Shoveling.  I was running low on valid reasons to yell at my kids, so I thought I could add, "Quit acting like a sugar whore" and "All that candy is going to turn you into a toothless freak" and "If you don't stop bouncing off the walls, I'm going to slap the shit out of you" into my Mom-of-the-Year verbal repertoire.

I was cruising my local Expired-Christmas-Candy-and-Second-Rate-Plastic-Eggs Store the other day.  Because I love my kids so much, I wanted to get more candy for my money.  And red and green kisses are for Christmas, which is also about Jesus, so it works.

The cashier and I were chatting about how important it is to spoil our kids with massive quantities of High Fructose Corn Syrup in Jesus' name. I figured we were on the same page-you know, the whole "Let's-celebrate-religious-holidays-with-ridiculous-amounts-of-sugar,-thereby-avoiding-the-true-significance-of-the-spirituality-of-the-holiday".  But then he said something to me at the tail-end of our transaction:

Cashier Dude: msfjbnscffdg.gdvfsif ifofdcns
Me: Pardon?  :::leaning back to hear him:::
Cashier Dude: He Is Risen!  :::beaming smile:::
Me: :::"deer in headlights" look::: Um, uh huh!
Him:  :::stunned look:::

Apparently, "Um, Uh huh" is the equivalent of saying "Thank you" in response to a heartfelt "I love you". Cashier Dude gave me the same look he would give a person that stomped on a kitten.  Total response fail.

Please tell me, what would have been an more appropriate response?