There are a variety of reasons for people to go vegan.
Basically one hectare of plant based foods can support almost twice the number of people as meat products can.
Meat is often more expensive than fruits and vegetables. Well in South Africa it is, don't know about the rest of the world.
There are moral reasons, as people don't like the idea of eating somethings that might have had a name.
There are plenty of health reasons, as vegans can be healthier than those consuming the average western diet.
I think there are also some religions that appose the eating of animal products. I'm not sure whether this is just vegetarian or vegan though. One example is the 7th day Adventists.
While the number of people self-identifying as vegan has been increasing it is still only a few percent. Veganism is somewhat overrepresented in celebrities so that is one of the reasons it is so visible now. I tried the strict vegan thing for a while but found it too difficult to stay on in Texas; just being a lacto-ovo vegetarian is hard enough but when you eliminate dairy and eggs it is hard to find much to eat at restaurants. If I was rich enough to hire my own vegan chef or if I lived someplace with trendy vegan restaurants it would be easier.
some might simply feel bad for the animals or just might have health issues... either way, they do have their own reasons for doing so & I respect them for doing what they feel is right to better their lives. As for me, I am not one, but i am trying to eat healthier...so certain things I wont touch, like all forms of white meat...(from bacon to ham...no chops no ribs...) Simply thinking about my arteries...but more power to others for their beliefs! :)
I believe it's becoming somewhat a trend. A few people start going Vegan to get healthy, or just because they choose to, and many others follow.
So, people are doing it to either to get healthy, or follow a trend in my opinion.
Its the way of the world...by going vegan, you are more likely to have longevity and sense of well being...