Air your kitchen and cabinets and put some of the following items in them (moths don't like them):
- laurel leaves,
- cloves,
- caraway,
- orange peels,
- black pepper,
so that you can feel their smell when you open a cabinet (if moths do, they won't go in).
They also hate lavender, but it's not a suitable smell for kitchen IMO, use it if you have problems with clothes moths, though.
Killing in self-defense is probably vegan, but I'm not sure about killing in fight for the food... decide it for yourself. I currently have two moths in a jar with dried vegetables, standing on the window, and I'm not sure what to do with them... I'll probably let them die of old age in there.
And oh, eating what you buy instead of storing it for a long time is probably the best strategy in moth-prevention.
