You bring up a good point. Depending on your business Facebook may or may not be the final destination. A good website is always great for information and more details about your product and service. With that said, Facebook provides the community to engage people who like your brand. At the end of the day, engagement is what sells. That is why virtually every Fortune 500 company drives traffic these days to their Facebook page and not their websites that they spent millions of dollars to build. They know engagement sells.