How might the application of purely democratic ideas to a functioning govnt. cause a problem for a large federal state?

people tend to bicker and not agree on anything. go to a local city council meeting to see what i mean. any city. with the Congress, you only need a majority agreement among the 535 members to accomplish the task of law-making. that is much easier than getting 300 million people to agree.

A purely democratic government would entail a pure vote including all people, of which the decision is made based on the majority. There would be no balance in this situation to account for even a large amount of minority voters. 

Dcalifornia they have the most people with 200+ people per square mile