I started out with this same question myself. Do I need a Facebook page? I figured promoting from my personal profile would be sufficient enough, but then I learned more about social media marketing and Facebook's algorithm for sharing content. After working for a local restaurant here in Elsa, Texas I learned a ton about what a Facebook Page can do for a business. A page puts you in direct contact with your audience. A Facebook page is a great place to to interact and share relevant content about your brand. It gives you a voice that can instantly begin to build your community. You can now offer fast customer service, use social clout from your customers to build your reputation and generate a community all in one place on your page.
The issue with Facebook pages are that organically you'll only be able to reach about 10% of your audience without paid ads. This is another reason why it's important to have your own website to send your online traffic to. I'll dive deeper into this in another blog entry.