Do you have friends, colleagues, and acquaintances who get in touch only when they need something? If yes, I'm willing to make a bet with you: You're not as close to them as you are to those who contact you just to check in.
My friend Rob Blatt calls this kind of friend a "seagull."Seagulls only sharetheir expertise when it serves their need. They have little regard for participating in community dialogue. And tend to ignore proper conventions. Here's a seagull in action.
The seagull in the video, "Sam" from Aberdeen, Scotland, was caught on videotape stealing numerous bags of cheese Doritos. The formal term for Sam's behavior--is "Kleptoparasitism" or the act of stealing food or other inanimate objects. Much like web surfers who usurp community discussions by changing the conversation to focus on themselves, Kleptoparasites "score" by stealing items they couldn't obtain otherwise--or by minimizing the time and effort required. They aren't nice.
To your success,