Marketing used to spread brand identities across several media in the age before the Internet. People read newspapers in the morning, kept their radios on in the car or in the office, and watched TV at night. Ad spending became more difficult to target as people became more mobile. The explosion of smartphones into several different sizes and operating systems initially compounded the targeting problem. The curse of Big Data for marketers is also a blessing, as those same mobile devices generate a stream of updates about a consumer's daily minutiae.
Enter the magic of Google's search algorithm and page ranking system. Google has figured out that some business listing services are simply more reliable in delivering high-quality solutions to consumer Web searches. The best business listings maintain a brand's ubiquitous presence in front of a target demographic, across multiple platforms. Brand ubiquity increases the chance that a consumer will select a well-positioned brand once they reach their ZMOT and make a purchase. It is no accident that the most successful business listing sites configure brands in rich snippet formats that resemble Google Places listings.
Small and medium-sized businesses (SMBs) cannot rule out business listings in their branding strategy. Google is powerful enough to reward advertisers who select favored keywords in ad spending and punish business listings that do not deliver attractive search results. Many skills in SEO and content marketing are interchangeable enough that SMBs can learn the basics. I do not believe the financial cost of an outsourced SEO effort is all that high, but the time needed to devote to the SEO learning curve may be a sufficient pain point for business listing services to solve. Business listing services may fill a gap for SMBs lacking the time or budget to optimize for mobile. Some of them may cost nothing at all.