Vegans avoid all animal products, afaik. It's much more "mission"-based than simply not enjoying meat, and with that mission comes their sense of superiority and need to resque all of us degenerate meat eaters from ourselves.
The few times I bothered to argue with one, I had to keep pointing out that I usually eat things other than meat, it's not like I roll in meat, and rub myself in it, but that's what they think.
Again, these are not simply "vegetarians", but they are on a religious/political crusade to save the universe against meat eating/ crusade to destroy all plants, since they clearly are the spawn of satan, and must die.
In fact, one of my funniest debates with one was when I became very existential about what life is, what perception is, and how a plant is a living thing exactly the same, with organs, inner and outer, genders, reproductive cycles - and for all we know - a perception. Flowers can tell between light and dark, cold and hot, they close up when it rains - they are reactive - and it is dismissive to simply declare their reaction to not be as important as animals.
Only one vegan admitted to me that it eventually comes down to emotion - that is, the emotion of the vegan: An animal screams and twitches - a plant dies in silence, and does not bother you with its death.
I love reminding vegans that plants actually stay alive after you chop them up, since their physiology is different from animals. This comforts them - or pisses them off, depending on how they see it :]
