Why don't we grow vegetables and something edible in our citites and common areas?

Mainly because growing a garden is a lot of hard work and requires a large amount of knowledge. You cannot just throw some seeds at the ground, wait a couple or three months and start eating. It is easy to maintain a green grassy lawn, a couple hours of mowing and watering every few days is just about all it takes. On the other hand a garden requires at least a couple of hours every day, if you have a garden large enough to feed a family of four, it would more likely require several people working several hours every day. Also there are no companies that you can hire to come take care of your garden like you can your lawn.

I don't live in the City, but I think it is great you put that question up.

There are so many possibilities for people to grow own food. From turning a lawn into a garden or even just container gardening on a deck or balcony. I guess most people just are not into it.

But if I would live in a city with a lot of smog, I wouldn't do it. Just to many chemicals would go into the growing veggies. But it is a great thing to do if you can. Not only does it taste better, but you safe money. And if you have kids you can educate them and maybe they eat more of it as well.

Growing vegetables takes more time and knowledge than just planting flowers and grasses. It would be great if most people had a vegetable garden or if instead of oaks and other common trees people would plant fruit trees.

Because the vandals would destroy the gardens. Or perhaps the thieves would steal the fruits and try to sell them back to us. All the dogs would hike their leg on the plants while their owners watch. Sad but true, I'm afraid it just wouldn't work.

Brilliant question, why dont you try it then tell us how it worked out for you.