Hi Jan

I get the feeling from your post that the guy probably would have known you were veggie/vegan?, I get the sense his stories were intended to provoke you or those in the conversation? I've noticed it a number of times, either to persuade people to compromise their own truth, or else provoke an over-energised expression in response (whether experienced inner or expressed outer). That's what he wants I think, to provoke energy, because for some reason it makes him feel big and in control. His aim is to press buttons, but its a clearly distorted ray1. He probably doens't really realise why.
As Open says to fight that isn't generally helpful. the right response can be,

Similar to what's been expressed on the post, I've found in those sorts of situations the best thing to do is to come from a place as unattached as possible. So if necessary and if possible soften your own tightness, and then allow expression to arise naturally. For some it might be (as Open suggested) to steer the guy to introspection and empathy, but often people aren't interested in the contemplation. If the invitation comes from the mind/intention or with extra energy he'll probably lap it up! There are other ways of expressing, like you might find yourself holding the space in silence, feeling the injustice, or might feel to express just your own honest opinion. The key being to be as 'unattached'(surrendered) as possible (I mean obviously don't deny your emotions but my experience is a more positive response will only come from engaging without 'extra energy', so while you feel your anger and sadness, you don't NEED to express it there and then), of course soemtimes the right response is emotional.

if I don't respond in the expected way and expressed my own truth instead. It really changes the dynamic.

best wishes

Ben