You can set up an environment where people live simply and happily, and invite others to come and observe. That is the only thing that will convince them to abandon their materialistic idea of happiness. They think that only when you have a lot to consume can you be happy, but many are very rich without being happy at all. And there are those who consume much less, but who are happier.
We need to demonstrate that living simply with a practice of the dharma can be very fulfilling, because until people see it and experience it, they cannot be convinced. In Plum Village, we laugh all day long, yet not one of us has a private bank account. Not one of us has a private car or a private telephone. We only eat vegetarian food. But we don’t suffer because we don’t eat eggs or meat. In fact, we are happier because we know that we are not eating living beings and we are protecting the planet. That brings a lot of joy. We are fortunate to be able to live like that, to eat like that.
There is a belief that unless you have a lot of money, unless you hold a high position in society, you cannot be truly happy. It is hard to let go of that belief until you see the truth that happiness is possible in another way. Seeing that will make the future possible for our children. So I think in Buddhist circles we have to reorganize so that we can show people a way of living happily based on mutual understanding, not materialism. Just a dharma talk isn’t enough, because a dharma talk is just a talk. Only when people see such an unmaterialistic community, when they see such a way of life, will they be convinced.
P.S. Will ask the GP about being a healthy vegetarian :)