"Mine was on an insufferably hot day in August 1985, when I got stuck for three hours underground — in a packed subway car with no air-conditioning on the train from Eighth Street — while standing next to a large and equally hysterical man eating a mayonnaise sandwich..."
She did not become afraid of mayonnaise, just closed spaces, and yet, I think, the mayonnaise sealed it. The mayonnaise made it horrifying. Why was the man still eating his sandwich if he was hysterical? The sheer perversity of it is so perfectly embodied in the whole idea of mayonnaise.