I don't understand why Google keeps going on about these glasses when their only purpose is as an always-on video camera. Why not keep it quiet until it can do

I don't understand why Google keeps going on about these glasses when their only purpose is as an always-on video camera. Why not keep it quiet until it can do what it is supposed to do. Because an always-on video camera is a pretty dangerous thing. Not only will you be routinely violating Civil Rights and Privacy laws but you open yourself up to assault by other people. Not to mention vigorous enforcement by the police.