Not only do people have different opinions over the same matter, but also will they express them freely, even if they are from the same race, same state/city, or even same party. Moreover, they share their different opinions in annoymous free online forums, as well as on national media, even those so-called "Main Stream" ones.
If you are really new to this idea, welcome to America - your country, not mine:)
Oh, btw, there were/are/will be always dumb people saying dumb things, even if they are politicians or people with high-education. OTOH, there are always smart people acting dumb and saying dumb things for various reasons.
Here are a few pieces arguing about the so-called "made in China outrage of Olympic uniforms", grabbed from a random google search first page result.