How important is the Sixth Precept to monks and nuns?
Here's an alleged quote from the Dalai Lama,


  After my lunch I come here to my office until about 5:30. Then at 6:00 I have my evening tea-as a Buddhist monk, no dinner, sometimes just a few biscuits or some bread. At that time I always watch BBC television. Then evening meditation for about one hour and at 8:30, sleep. Most important meditation! Sleep is the common meditation for everyone-even for birds. The most important meditation. Not for nirvana, but for survival!


In other words he "eats" but doesn't "have dinner".



In this video Yuttadhammo Bhikkhu explained why he prefered to eat once a day.
It's noticeable that both his companions laughed at time 12:15 of this video.