While those of us on the leading edge of the green movement may be perfectly happy to live in a house that looks different, most people feel more comfortable with a home that "fits in" with the neighborhood. These folks aren't going to do anything that looks weird to them, such as putting lots of exposed piping on the roof to collect solar hot water, and they're not going to do anything that they perceive as ugly, such as installing a bright blue rain barrel. (And they may be prohibited from doing so by homeowners' associations and CC&Rs intended to preserve property values.) So these folks may be just as concerned about the environment as everyone else, but they also want to get along with the neighbors.
That's why we're looking forward to more green products in "disguise" like the Velux Solar Hot Water Collector.