I don't know you.
Alex asked for arguments against veganism.
The best is we eat animals because we can.
Just as they eat us when they can.
This "might makes right" is the default posture of the universe; The winner can then post-hoc moralise as much as they like, and their arguments win because the loser has been eaten and can't respond.
All human morality is us trying to lift ourselves out of this base state of the universe -
Veganism is such an attempt,
As are all ethical pursuits.
And so they are the very definition of virtue.
Still, Alex asked, so I answered.

But sure, talk some more about shooting me.