You need some background information for this one:
One of Britain's favorite family dishes is Shepherd's Pie - minced lamb, carrots, and gravy, topped with mashed potato. When I was at school, I was taught to put sliced tomatoes on the top of the potatoes before serving - I went to a very posh all girls grammar school (a very long time ago). Okay, on with the story:

After a day spent drinking, Michael Garvin cooked his brother John a shepherd's pie, for which he expected a grateful response. John, however, was less than impressed - he wanted his dish topped with sliced tomatoes. As a trained chef, Michael disapproved of the sliced tomato topping, feeling it a wholly inappropriate garnish.

The two brothers could not agree on the niceties of shepherd's pie presentation and, to ram home the point that tomatoes were de rigeur, he hit his brother over the head with a shovel. When chef, Michael, still wouldn't concede the point, John threatened to petrol bomb the philistines apartment.

John was arrested and spent the night in the cells of Blackburn police station. At the subsequent court case, he admitted a breach of the peace, fined $400, and was bound over to keep the peace for 12 months.

By the way, in England it seems everybody has an opinion on the topic of shepherd's pie; District Judge Peter Ward told the defendant that, in his view, there was no need for a layer of tomatoes on a shepherd's pie.

Maybe it's a class thing?

Daily Telegraph