It’s important for space advocates to understand that this opinion is held by people not because they are hostile to space exploration, but because they lack sufficient information about it. Thanks to the media, which generally covers space-related stories only when something goes horribly wrong, a general impression has been created that space exploration does nothing more than produce a rather small amount of scientific information, of no practical use to anybody, at enormous cost to the taxpayer. Once people have settled into a comfortable belief about something, getting them to change their opinion is far from an easy task.

http://www.thespacereview.com/article/898/1