I understand where a business is coming from. The goal of a business is to sell a product. Every move it makes, every step it takes (h/t The Police) is calculated and designed to reach that goal of making the sale. A business should have marketing systems in place that do this; whether T.V. or radio spots, fliers in the mail or email. A social media marketing campaign should help support these other systems.
Facebook is still the top social networking site, and if you are a band, it's a smart move to have a Facebook Page. Making some grand statement about how having that Page doesn't matter is a disservice to the local bands that are out there working their tails off for a craft they can only hope to make into something lucrative. Not everyone can be the next Gin Blossoms or Kongos, but exposure and support everywhere you can doesn't hurt.
Being your own brand has its own set of challenges. It’s the first and foremost way you will advertise your business, always. When I first made this decision, I had a small panic attack. I’m a very open person online. I pretty much communicate online as I would in person, what you see is what you get. No one has ever said to me “you are not how I expected you to be!” when they meet me in person (other than the occasional “you’re shorter than I expected.”). I’m actually proud of that, because it is my belief that you should just be open and honest, good or bad, in how you present yourself online. But that is a different post for a different day. However, I noticed I was beginning to be a little more conscious of how I interacted and presented myself online.