We also need plants to eat. We don't need direct access to the plants to eat them, nor do we need direct access to plants to benefit from carbon dioxide to oxygen conversion. I'm not aware of where the plants I eat come from, most of the time. I'm not saying I don't need plants, I just don't necessarily need to live among them, but I like being able to see plants frequently. I have no desire to have my own garden though, I would rather appreciate nature in a public place where everyone can enjoy them, such as parks and along streets.