Does anyone have a good explanation of the mentality of these media organisations? There are good examples of how relaxing DRM and making it easy to purchase co

Does anyone have a good explanation of the mentality of these media organisations? There are good examples of how relaxing DRM and making it easy to purchase content makes you shed loads of money. E.g iTunes Music Store. Why aren't they just concentrating on how to make more money? Are these actions really more productive than acquiring more customers?