This is a great question. It might seem that the magazine, Rolling Stones is only about music, but to think this would be completely wrong. It was started in 1967. It seeks to influence its readers in various ways. Let me name a few of them.
First, there is hipness or a cool factor to the magazine that is rooted in the spirit of 1970s. Therefore, it attracts a certain type of readership - usually people from the 1960-1970s (not to mention all of the younger new readers) and those into music. Many people fall into this category, as you can imagine.
Second, there are many articles. Many of them, to be sure, are about music, but there are many articles about culture, politics, and international affairs even. Therefore, they are spinning an ideology, a decidedly liberal one. Moreover, over the past decade or so, the magazine has become more and more respected and at times they get incredible interviews, which shape the mind of its readership.
Third, because the magazine has a "cool" feel, it is able to shape it readers with advertisements. In the end, magazines need to sell. For this to happen, they need to generate money through advertisements.