I used to date a vegan. They were great. I ate lots of vegan food. Some of it was good, some of it wasn't. I still end up eating vegan meals often, but not intentionally. They suffered no hypocrisies and we often discussed the nature of their beliefs without incident.
There are several flavors of vegan hypocrisy, and they all stem from a lack of philosophical consideration:
* "I won't eat anything with a face."
* "cow farts"
* "Everybody can afford to be vegan."
* Using "The Jungle" as a proxy for modern slaughterhouse conditions. (Heck, thinking about it, even "Fast Food Nation" is starting to become a little dated.)
* Vegans with cats or dogs as pets. Dogs do poorly on vegan diets, while cats must eat meat; there's often a lurking contradiction about animal rights somewhere in there.
* Vegans who crush house spiders.
* Introducing vegans to Jainism is always hilarious; they almost never have heard of Jains and are surprised to learn about people that are even more religious about animals and morality!
That all said, it's been nearly a decade since I've run into anybody like this, and perhaps it is a juvenile form of veganism that only manifests at universities and bars.