> I believe we've been told by the courts repeatedly that we should have no expectation of privacy out in public.

This is not true. The original "reasonable expectation of privacy" case was about tapping phone booths, which are in public. And the way the law works (or is supposed to work) is that the reasonableness test is based on a typical person. What does or does not violate a reasonable expectation of privacy should not be assigned to us by judges.