My book club nearly came to blows over a character's sandwich choice

We were discussing a novel set in 1990s Seattle, and someone said the main character ordering a tuna melt at the diner was a sign of moral weakness. This sparked a 20 minute argument about food symbolism that got so heated our host had to pause for more wine. I realized we were all just projecting our own weird lunch habits onto fictional people. Has your group ever fixated on a tiny detail like that?