Some fast-food chain advertised chocolate cricket shakes last year. So, out of curiosity, I looked it up. I found out that there is a company that raises crickets in sanitary conditions, then "humanely" freezes them to death and grinds them up to make a powder. It takes hundreds to make a pound of the powder.
A) I do not see how freezing them to death is humane. Even if they are "flash-frozen" there is still a small lag time between the time they are submerged and they actually freeze solid, and there is the possibility of pain during that time.
B) If someone's motivation to avoid eating animals is to avoid killing them, I do not see how killing hundreds of crickets is any improvement. Instead of one life providing for many meals, it is hundreds of lives for one meal.
C) The thought of eating crickets or any other insect is just plain disgusting.
I think the idea that they are arguing is that you spend energy on raising the grains fed to the animals, and it takes less grain to feed a person. However, I will agree it makes more sense to kill one animal or a fish to eat it as opposed to many insects.