Depends on your target market and your overall budget.
For a Dog Walker Facebook will be their main outlet, they'll likely get reviews and ratings, be shared by friends and family and build their business up that way.
For Apple, it's another channel.
As with any marketing - for businesses it's about ROI, is it worth the investment? Are the target audience there? Can we see growth? Is our goal to grow the social media channels etc.
I'm a marketing manager within a retail company, social media is one of the outlets used but it isn't the most important. The products being sold aren't allowed to be advertised through Facebook - so it's just a method of re-engaging / answering questions.
