The bike manufacturers generally make only the frame. They buy the components from Shimano, Campy, Mavic and others.
Some manufacturers make a really basic frame so it is inexpensive and hang better than usual components on it for its price point. Other manufacturers make sophisticated frames that are costly so at the price point, you take a component hit. Often the same manufacturer will offer two models offering both of the above mentioned approaches.
The thing is that competition is very tough in the bike business. The LBS will not carry bad bikes. They don't have to. Bikes with similar components and similar frames (like low end carbon fiber race bike) are very similar.