I once believed the same thing. I work in a vitamin store and I would say that 99% of the shoppers are meat and dairy consumers. My point is that it is very difficult in today's society to get all the nutrients you need to stay healthy. The standard American diet certainly does not offer all the essential nutrients to maintain health. I even know meat eaters that have to get b12 shots, so your argument doesn't really hold a lot of weight. I would rather only have to supplement one nutrient than a host of others. Which I do only supplement one and it's b12 and I get all other nutrients through food.