1. Using Percy Schmeiser as an example is a Really Bad Idea, because anyone who is ever worked with a canola crop knows he lied in court. Canola seeds are little black balls; they are not very aerodynamic. Over 90% of his crop was Roundup-Ready(RM). A wind strong enough to blow that much seed from a neighboring farm would also have removed the topsoil!

2. People who produce new varieties of plants using conventional breeding techniques can "patent" those varieties. There's a form of intellectual property called Plant Variety Rights, which is modeled on the patent system. It dates back to 1970. Some people believe the PVR system has significant flaws.

(Incidentally, canola was produced from a plant called rapeseed by conventional plant breeding methods.)

3. Here in Australia, not many farmers are using bio-engineered seeds for an interesting technical reason. Good farmers usually get their seed from plant breeders, who are continually improving their product using conventional breeding techniques. Bio-engineering and breeding both produce only a handful of seeds; you have to grow a crop with those seeds, grow another crop with the resulting seeds, and so on, until you have enough seeds to sell. This generally takes at least two years. Since the bio-engineers start with publically-available seed, the seed they produces will be two (or more) years worth of breeding behind the conventional seed — and those years of conventional breeding generally produce more advantages for farmers than the bio-engineering!

4. But third-world farmers do get much better yields from bio-engineered crops. Because few third-world farmers can afford pesticides, bio-engineering pest resistance into crops can greatly increase production. In fact, stopping third-world farmers from using GM seeds is causing millions of unnecessary deaths from starvation.