I’ve worked for two companies during the social media era and both have used it almost exclusively for one-way bullhorn marketing efforts, and even with ambitions that low they’ve mostly failed. Social media presents unique new opportunities to reach customers, engage audience and build community around your product or service. Nevertheless, of the millions of companies with a Facebook page or a Twitter account, only an infinitesimal percentage of them are using the technology well.

In the newspaper industry (where I worked before getting into restaurants), newsrooms across the country were constantly abuzz with discussions of Facebook and Twitter, Foursquare and Flickr. But the bulk of the conversation was always about using social media as opposed to becoming a social medium.

(Finally, three years later, The Washington Post Social Reader, flawed as it may be, attempts to get it right. Is it too little too late?)

At my current gig, our restaurant chain’s Marketing Director maintains a social media presence on Facebook and Twitter, but misses the point by using it only for one-way broadcasting. The nice thing about social media — indeed, its defining feature — is that it’s interactive. If we never respond to our customers’ comments, if we never ask for their feedback, if we never engage them in discussion of our products or service, we’re putting a converse twist on Maslow’s law of the instrument: If all you have are nails, every tool looks like a hammer.

It’s important, too, to consider the reasons you feel more connected to certain businesses via social media. I’m willing to bet they act like human beings, maybe even put their own faces on their accounts, and that they’re allowed to introduce at least a small measure of personality into their tweets or Facebook posts. I’m guessing that the information they share doesn’t read like an official press release or like it was prepared for them by a team of publicists, but that instead it reads like their own thoughts in their own words. I’ll bet there’s even an occasional opportunity for discourse with someone who would otherwise be completely inaccessible to you.

Would it feel the same if they hid behind a generic company logo? If they spoke only in officially sanctioned platitudes? If they never responded to your questions or comments? Would you bother checking their feed at all?

In any business, the ultimate goal is to create shareholder value, but how do you do that? You do that, of course, by meeting the needs of your customers better than your competitors do. Given that, it seems like a decent idea to get to know those people a little bit, doesn’t it?

Not long ago, businesses had almost no connection whatsoever to their customers. They relied on mass markets and mass-media communication to target huge swaths of generic “customers.” They focused on marketing products and services or creating transactions rather than on cultivating relationships.

What did this lack of meaningful engagement give us? As customers, it gave us things like planned obsolesence, so-called “negative externalities” (a k a pollution), false advertising and the burgeoning (dis)service and (mis)information industry. As business people, it gave us customers who were about as loyal as Judas.

Social media changes all that — or, at least, it could. Businesses now have unprecedented tools at their fingertips for understanding and interacting with their customers, not just as broad demographics but as unique individuals.

I say “unprecedented,” but in a way it isn’t. Before the industrial revolution came along and customers were suddenly reduced to stereotypical consumer segments by faceless behemoths whose employees were alienated corporate cogs, there was a time when local business people — often our friends and neighbors — worked hard to gain our trust and meet our needs.

For instance, as a teenager I frequently shopped at a local record store where the owner, Pete, and his employees, Marshall, George and Jen, all knew my name, my tastes and my budget. I’d walk in the door and they’d cue up a CD they were sure I’d like, and eight times out of 10 they were right. Amazon.com can make recommendations like that to me today, but I have no relationship with Jeff Bezos or anyone else at his company. If another online retailer offers a better price, well, guess what? Smell ya later, Amazon. On the other hand, I’m still friends with Pete and Marshall 20 years later and if their store was still open, I wouldn’t shop anywhere else.

You could argue that building relationships that strong is too tall of an order for most large businesses in today’s globalized economy, but social media says you’re wrong. (Or, at least, you’re doing it wrong.) And, really, can businesses afford not to take advantage of this opportunity? There’s something in it for them, too.

That’s the nature of reciprocity. The consumer Cold War is over. It’s time for businesses and customers to start scratching each others’ backs again.