Recent studies in Germany (if I remember correctly) have shown that GM crops alter the ground in which they are planted. They harm the organisms in the soil quite badly and significantly and irrepairably alter the microbiological balance in the soil. The long term fertility of the soil is also harmed.
So maybe your gentech produces a short term gain. The long term, which we are yet to see, promises to be quite ugly. In the meantime, the corporate execs have their money and have run away.