I've also encountered arguments along the lines of "there's this other suffering you _aren't_ preventing".
Emotionally it has the same feel as the drowning child argument[1] by Pete Singer. That argument engenders a feeling of hopelessness for me, because I can't assail its logic but it implies a vast array of suffering for which I am morally culpable.
I think meat eaters feel similarly. When faced with the cognitive dissonance, they shrink.
Now, I mostly shrug and say, "I'm doing the best I can."