Often we will see homes that just have accent lighting. If these are the only source of illumination then what is created is called the "museum effect," where family and guests feel less important than the objects in the space. What the professional photographers are doing is to add supplementary fill light to balance the illumination in the shot. This creates the illusion that the recessed fixtures are also adding ambient light for the space.
The most effective lighting design occurs when various types of lighting are layered together to create spaces that are both inviting and flexible. The decorative lighting is what I like to call the architectural jewelry. It welcomes family and guests into the various rooms and helps create a sense of place; especially in open plan homes where rooms tend to flow together. The ambient lighting is the alluring indirect illumination that softens the shadows on people's faces and fills the volume of a room with illumination. These varied lighting elements will work beautifully together, like Brad and Angelina.