But then they wouldn't be vegetarians. So, they're altering their diet to help save the environment (much as the carnivores are being asked to do).
And do you know how much energy goes to making one of those neighbors?! Yeah, but that cost has already been paid - no way to recover it. We can, however, reduce
future energy/water expenditures by reducing the demand for, ummm, more
traditional meat products.
Mmmm... soylent greenburgers...