I sincerely appreciate your naivety! However, imagine this scenario. First, hopefully we can agree that those in power, are almost always sociopaths. Only the most cut-throat people can stomach making it to the very top. You simply can't be uber-successful AND have a conscience. Those are mutually-exclusive.
So, it should be a given that this world is nothing short of a "game" for these sociopaths to play. OK, so let's play out your scenario from two sides:
The Monsanto side: they create seeds which only last one season. This way, farms have to keep coming back and buy seeds each year. They patent the seeds, and have ravenous attorney's and research departments which scour the food supply for infringement. Meanwhile, they lobby to have laws and regulations put in place to squeeze out competition. Because of the monopoly, they can charge more, which means food gets more expensive. Monsanto is happy!
The Gubmint Side: some congressman gets a fat lobbying check to help pass some legislation for his Monsanto buddy. Not only is it good for the congressman (money-wise), it's good for his buddy, PLUS food is getting more expensive so that means higher taxes OR more financially-strained people.
"Why in the world would the gubmint WANT people to be poor and/or starving?", you ask. Well, you can give poor people free stuff. Then, at election time they HAVE to keep voting you into office or else they'll lose all of the their free stuff (welfare, WIC, section 8, etc).
So, morals aside - there is NO downside to Monsanto getting their way. They are securing their profits, the gov't is making more money AND securing more "customers" for the welfare state. My point is, when you look at something like this without morality, it's not a "problem". So, this isn't a problem, to them.
I'm not quite sure what you mean that "the people" have power, but that simply isn't true. At this phase of humanity, we are merely cattle at a slaughterhouse. We out-weigh and out-number the butchers, but the systems that have been put in place are inescapable. For this scenario you are talking about, there are only two outcomes: the system collapses (which is not unreasonable, considering our currency, and foreign overreach... see: "The Fall of Rome" for the example we're following!) - OR, things are going to get worse. There will be some big false-flag events to unite the North American Union - who is already in bed with the EU and the UN, so then it will be that New World Order versus: 1) the crazy middle east 2) China and 3) Russia. That will be resolved in a World War, where the "west" will likely be the winner. Then, you'll have one... unbelievably corrupt "one world government" with a planet full of slaves.
Our future is all but a foregone conclusion. Do you have any reason to think that it isn't?
p.s. Sorry for the downer post! Don't forget to check out /r/babypigs if I bummed you out!