All sort of companies sell (sponsored Tweets, for example) on social media, so a better question is should you? In my opinion, the answer is no.

<strong>Wedding crashers</strong>

Think of it this way: you are at a wedding reception. You are busy chatting with relatives you haven't seen in ages while enjoying one or two glasses of champagne. Then, someone (think of this person as a wedding crasher) pops up, out of nowhere, and starts discussing health insurance options with you. First, you know this person is not invited to the wedding. Second, this person is a buzz kill. Right?

<strong>Time and place</strong>

Same thing happens when you are on Facebook or Twitter and someone you don't know is talking to you about something you don't want to discuss right then.  And the truth is you may be interested in the product or service being offered, but the time and place are all wrong. It is wrong because you are on social networks to be social. You are not there to shop.

This is not to say you can't market or communicate with target audiences on social networks. If your emphasis is brand awareness or image building, I think social networks can be hugely helpful. But selling is a "push." And people don't like to pushed when they are relaxed.

Perhaps this a personal bias of mine, but I don't like being sold in general. The other day I was