Question: How should vegetarians and vegans reply to meat-eaters who claim that plants feel pain?
Answer: Plants are definitely lifeforms, but are not complex enough to be fully sentient. Though they are capable of having some natural responses to external stimuli, this does not adequately prove they are sentient. Even if they are equally as sentient as animals, meat-eaters who eat animals indirectly eat much more plants than vegetarians and vegans, as the consumed animals need to eat many plants in their lifetimes to fatten up for producing meat. For instance, as feed conversion ratio, it takes about 10 pounds of plants to be converted into 1 pound of beef. This means beef-eaters eat at least 10 times more plants than a vegan. Many other precious resources like water and land have to be used too. In this sense, there is more wastage of food, lives and resources through demand for meat.
Related Article:
What If Plants Feel Pain Too?
https://thedailyenlightenment.com/2010/11/what-if-plants-feel-pain-too