‘Sup?
At first, I thought this would be about saying “soup” with a funny accent. Perhaps they had been to Olive Garden frequently and enjoyed the Zuppa Toscana soup. (Which would make sense because if you’ve had that particular soup from Olive Garden, it’s excellent.)
I have been looking at 7UP my whole life, and I never realized that the seven could be pronounced as a Z. But now that someone has pointed it out, I can’t unsee it. My brain is going to start wanting to call it “Zoup” from now on too.