Fighting proper labeling of GMOs is a dick move, and something I agree with the eco-spags about. I think it's sensible to be cautious about new foods being created, but the hysteria is uncalled for.
I do outright oppose the existence of one class of GMOs: the pesticide-resistant and pesticide-containing ones. Peak oil isn't going to not happen just because the only people whining about it are crazy, and right now all our pesticides are based on petroleum. Wasting time and money creating food that will be useless in the foreseeable future is just fucking stupid.
I don't know if you lump this in with the business practices, but the loss of biodiversity in our food supply is really worrying. We're down to single digits of corn species, there's a very real possibility when shit gets that narrow the entire population could be wiped out and there would be no more corn, ever.
I can see that pesticide resistance having to do with oil use, but pesticide containing? It's manufactured by the plant, and takes the place of synthetic pesticides. Not really an argument for or against, just asking for clarification.