A ten-minute interruption occurred last week on an AA flight (BDL-DFW), hub-bound so the FAs were particularly delay conscious.
Flight was fully boarded, and the gate agent was finalizing paperwork with the cockpit, when a 40-something woman from coach marched up the aisle and talked in an agitated way with each FA. Once I started listening more closely I realized it was a nut allergy rant. AA doesn't serve peanuts: neither among the coach snacks nor in the first meal service. The FAs repeated this several times.
The woman then shifted her complaint and demanded that the FAs give a public address instructing all passengers on the plane not to eat nor even to access any peanut products. They declined this request, but said she could negotiate with the passengers seated near her. The pilot then emerged and said do you want to fly with us today or not, I need to know now. She retreated back to coach and the flight went smoothly from that point forward.