In theory, it is, but in practice, the Green Revolution hybrid(very carefully cross-bred) seeds required you to get new seeds every year, because the seeds you'd get from your harvest would be cross-pollinated improperly. GMO could possibly bridge this gap, but you don't want GM crops cross-pollinating with everyone else's, if only because if it cross-pollinates with an organic farmer's crops, the latter can lose their organic certification. The solution to this is the terminator gene, that makes it impossible for such a situation to happen.

I'm not going to support Monsanto's IP actions here, but they aren't pure evil the way, say, De Beers is.