You don't force a government to be democratic, you force the people to be democratic. Their voice will change a government (either through peaceful or revolutionary means).
"Seizing" control over a government always means that one person/group seizes control, and I doubt they would really want it to be more democratic once they taste power.
You can't just "nullify" laws that benefit a specific group of people because those laws were made by a corrupt government that isn't for the people.
Overturning a government is far easier than overturning an entire population. Just try to do it. Say to the American people, "Let's take the government back for the good of America" and you instantly get people arguing over which the right way is. Most can't even agree on which part of America matters more.
While people will want to hold on, if your mission is truly "for the people" from the beginning, are you saying that there is 0% chance that they will act in the people's best interests? Take former President of Uruguay José Mujica for example. His
lifestyle reflects this.
If you seized control of the government, you could. Take Monsanto, for example. They're a huge and wealthy company that has unprecedented power that can control politics above and around it and a great deal of an American regional economy, to a lesser extent, the global economy. They don't need subsidies placed on corn and soybeans, amongst other products. Regulations set standards for crops and seeds that Monsanto has already achieved, but it makes difficult for other bioengineering companies to achieve with their limited budget and the uncompetitive prices of a larger and more influential competitor. If you modified the regulations to still allow safe products and removed subsidies, the huge companies would not suffer, and other smaller companies would have more opportunities to find a niche.
