And the big problem is that the seeds contained in the produce is not propagatable (if that's even a word).
That means you can't grow your own vegetables from the seeds contained in these foods.
When you combine that with legislationt that increasingly disallows people from growing their own background gardens (why do you think the media makes such a big deal out of MoBama's garden), the result is way too much power in the hands of too few sources.
To protect intellectual property - which under the Constitution they have a right to do.
If they sold GM soy to a farmer ONCE, and he could propagate his own seeds - wow - they got ONE sale out of the guy. And then when he decides to sell his seeds?
You think China or many many other nonintellectual property right recognizing nations (usually because their populace has no intellectual property worth spit) would enforce their patent - or would they purchase ONE copy of the GM crop and reproduce it - like they do with computer software?