When I saw your question, my first thought was to ask myself, "What is popular science?," aside from a magazine, that is. And I would have to say that popular science places an emphasis on application in people's lives, in opposition to "pure" science, which often takes place with no thought of application. Popular science articles are written in a way that people without scientific backgrounds can understand, summarizing important ideas that can be used by everyday people.
Popular science has tremendous cultural value for three primary reasons. It can generate new scientific exploration, it can creat a knowledgeable citizenry who can use that knowledge to make intelligent voting decisions, and it can be put to use in one's life.
First, learning about science can generate new ideas by sparking curiosity and conversation. It is not just scientists who can get good ideas and want to explore them. You might read an article on a topic that will make you want to do your own research or talk to a friend about an article that triggers some new idea for your friend.
Second, popular science exposes us to concepts that we need to understand in order to make good decisions on a local, state, and national level. The more people there are who understand science, the better off we are as a nation. A recent example in the news is the discussion among Republican primary candidates on the cervical cancer vaccine. There are candidates who have chosen to ignore the science behind the vaccine. Another example is global warming, which some politicians completely dismiss because of their lack of scientific knowledge or their contempt for it. It is up to us to inform ourselves, so we can let politicians know that disregarding science is a very foolish idea.
Third, there are many applications for popular science. I have provided a link to an article on birth control for animals. I know that in my community, we are overrun with deer, which are suffering from an overpopulation problem. They are a hazard on our roads, and they are starving to death. This is an idea that my state could apply to a major problem.
Poplular science articles are culturally important. They give us new ideas, they help us be better citizens, and they be applied in all sorts of ways to improve our own lives.