Oh certianly a lot of people would grow. But the shops would of course have seeds with "samples" or vice versa.

Not to mention, not many people have adequate space for growing, and obtaining space isn't always an option. For example, our house, there isn't really a good place, not in a 3 bed 2 bath, single story house with a partial crawlspace. And two kids, two cats, and too much shit to do a closet grow. So, we'd still be buying until a few years from now when we can afford to move and chose a space just for growing, either indoors or outdoor (probably in)