Suffice to say, why is there a necessity for soooo frikkin many churches, all reading the same book? Is there that much confusion as to what jesus said? Is there that much confusion as to what you are supposed to do to please god? Would not just one church be sufficient?
Various churches often do not agree with certain interpretations of the bible, which is why there are various denominations.
If we read the letter written by Thomas Jefferson that inspired the phrase and belief of the separation of church and state, the spirit of that letter was in a time of competing denominations. Many fears arose that the United States government would take an official stance on Christianity, thus nullifying one large reason for seceding with England and its Church of England.
In an attempt to assuage those concerns, he wrote that the government should take a neutral approach.
Protestants generally do not believe in a papacy of men acting as vicars of Christ. There is no hierarchy to rule them, so they have all branched off on their own. Either congregation agrees with the interpretation or they find a new church.
That is why there are so many churches in America.
"Facts are stubborn things; and whatever may be our wishes, our inclinations, or the dictates of our passions, they cannot alter the state of facts and evidence." --John Adams