I'm a fat vegetarian, and I've been a fat vegetarian for most of my life! I know lots of fat vegetarians. There are lots of "nutrient dense" vegetarian foods, shall we say? It's ridiculously easy to get -enough- nutrients as a vegetarian. On the contrary, I find that I generally eat a more nutrient-diverse diet than many of my omnivorous friends, who have never really had any reason to give thought to what they eat.
It seems popular that when vegetarianism, and especially veganism gets brought up, people start bringing up examples of unhealthy vegans they knew, or questioning how they get enough nutrients. What I find amusing about that is that there seems to be some assumption with this line of thought, that meat eaters are all eating well-balanced, nutritionally satisfying meals, which is definitely not the case. In fact, you're more likely to get asked about your nutrient intake as a veg* than you are as a low-calorie dieter! I probably consume 2000+ calories a day, and you're wondering where I'm getting my protein!? No worries, my friend! It's in there!!