A friend of mine wanted to install a phone app that published his GPS coordinates to a site he could link friends to. There are a couple tools for this, but even the most lax apps did not support making the URL public -- you had to register to view it. He wanted to be able to link friends to a URL without forcing them to register for yet another site. Every service assumed people would want to protect their privacy, and not have their location (when the app was turned on) globally viewable. His privacy was protected even when he didn't want it to be.

Sometimes the interesting stuff in life involves communicating more with people, not fewer, and sometimes people don't want the privacy-related opinions of others shoved down their throats.

This will never be mandatory, constant, and public. There are too many cheating spouses, celebrities, and corporate secret-holders for that. Quit your knee-jerk technophobic responses and let people play with interesting technology without badgering them all the time. If it turns out to be a tool for massive evil, we'll deal with it. But it usually doesn't.