The music industry has changed a lot in the last 10/15/40 years. Pretty much most, if not all of us have our own little home studios built up which we wouldn't have been able to do probably even 15 years ago. Certainly not to the quality we have now. You don't even need to have come from a musical background, or even know how to play an instrument to become a music producer these days. This means that there are thousands of people sitting on their computers writing very similar stuff and uploading it online and there's too much to sift through. This puts a HUGE emphasis on your marketability and your online presence. People need to know who you are! You can be a musical genius but if you have no online profile then people will never know it. I remember hearing somewhere that you need to put in about 5 times as much effort to your online profile than you put into your music in order to get yourself out there successfully. If you're on a label, then all your PR is done for you. But when you're not, you have to do it yourself and the internet is the best place at reaching a huge number of people.
There are bands that have done this, who are completely independent but have built up such a fan base through their online profile that they are able to sell out nationwide tours and aren't actually on a label. Aganst the Current (I think they're on a label now?) sold out a tour by killing it on Youtube for example. It's worth noting as a meaningless fact that one particular Indie band that i forget the name of actually ended up in debt after their sell out tour because of equipment hire, costs, travelling, venue hire, paying the lighting guy etc etc and what not. It's certainly possible for your music to be worth something beyond you and your friends, but it takes a great deal of work to get on top of the competition.