Is vegetarianism compulsory/obligatory in Nicherin Buddhism?

I recently visited Japan and went to see a Nicherin Buddhist monastery and temple in Tokyo. There they were preaching that Buddhism is not just for the Japanese or Chinese or some particular race, it is for the entire humanity. The chief monk their would barely speak English but he said he is a follower of Buddha, Nicherin and Tanaka Chigaku. Then he invited me to his home and his wife served fish sushi and chicken meat balls for both of us! I ask, 'You are a Buddhist and an ordained monk, do you eat meat?' He replied that even Buddha and his followers ate meat!