Taking in food is to survive, you can do it in humane way or other ways, most animals kill to eat, and quickly sedate the prey (less trouble, no concern of pains I assume).

As for plants, we assume but do not know for sure scientifically that they do not feel, we assumed the same for insects which can feel pain for sure.

Then if plants can feel we do not eat them? Hell, we still do, as I said, we eat to to live, we have to.

Those vegetarians who eat plants to avoid killing lives are ignorant, period.