Mostly the young are interested in letting others know their physical location. Others are reticent for safety reasons, or against providing too much information. The New York Times reports:
“Internet companies have appropriated the real estate business’s mantra — it’s all about location, location, location.
But while a home on the beach will always be an easy sell, it may be more difficult to persuade people to start using location-based Web services.” [...]
“For now, many people say sharing their physical location crosses a line, even if they freely share other information on the Web.”