I believe that the VAST majority of vegans do not consume any animal products simply because they do not want to. There are many possible reasons and I think with most vegans it is a combination of reasons. They make this choice for themselves and do not try to dictate to others. These people know that all large scale food production involves, directly or indirectly, the deaths of animals. Like them though, I can see a big difference between basically animals being killed as a side effect of food production and breeding and rearing animals solely to be killed for human consumption. The "pests" that die were not bred intentionally SO they can be killed.
There are though, a minority of "vegans" who see themselves as morally superior, who talk of "saving animals" and avoiding any kind of cruelty. They claim that a vegan diet will prevent or cure just about any disease known to humanity. They claim meat, eggs and milk are injurious to health whilst ignoring the fact that the chemicals used in crop production and not absorbed by the plants find their way into waterways and then into the food chain.
I'm not sure that this is hypocrisy though, I think it's more immaturity, ignorance and stupidity.