First, vegetarianism reminds people too much of the ascetic rigors of fasting monks; and secondly, the price and variety of vegetable ingredients are not as great as those of meat dishes--so vegetarian food doesn't seem the proper way of treating a guest to dinner.
一來是素食常讓人聯想到出家人所吃的齋飯，有苦修意味；二來是一般素菜身價不如海鮮肉類，材料變化不如葷素混用來得多，難免令人興趣缺缺。