I wonder if its more based on income security, maybe they feel insecure spending so much on meat when most no longer earn an income and live soley off what they already saved in super/investments etc. I know my parents eat a lot less meat these days (they are in their 60s) as opposed to yesteryear. My father is not rich, I would say middle class, but he has often complained about the cost of food being absolutely ridiculous, and he refuses to buy it at that cost. I know he could afford it, but he chooses not to, he and his friends also grow allot of back yard veg etc which my family get the benefits from. I really think its more of a stubborn stance taken by elderly folks not to consume expensive food, and meat is about as expensive as it gets. Just a thought.
EDIT: And how could pensioners afford to eat much meat, they get stuff all. Maybe they just eat the veg as its cheaper mostly.