For some people, it's not so easy...
For a start, being a student, it is near impossible for me to achieve a perfect diet, I'm also very social, what do you expect me to do after a night out? Prepare the most perfect vegan meal? For me a pizza is more like it.
I did this once, using diet to cure my acne, it actually worked, but I lost so much weight, I couldn't go on much longer, I enjoy the freedom of now being able to eat whatever I want.
I'm currently on a weight gaining diet consisting of a lot of meat, protein and other good stuff in combination with a good workout, and I tell you what, it's very satisfying.
I would respect most vegan people more, if they didn't try and force their opinion on other people.