Theravadin Buddhism itself is not vegetarian. It encourages people to be content with whatever food they get. The Buddha, and all the monks and nuns, went on alms rounds in the morning and they would simply open their bowls, the villagers would put food in. And the Buddha, and the monks and nuns, would be content with whatever they were given. Whatever it was, they would try to be content, happy that they have food. Just like the food reflection that we teach here. To reflect that, even if you're vegetarian, you're still in the process of eating food in which other living beings have died. So Theravadin Buddhism is not vegetarian.