"We aren't being told everything obviously, and why should we be?"
Exactly.
Quite apart from the fact that it must be incredibly distressing for the family to read the general public's theories, it always strikes me as incredibly arrogant of people to assume that they know enough to invent a theory in the first place.
Yes, obviously family and friends will be closely questioned in the search for evidence about what has happened. Yes, there will no doubt be certain facts which haven't been divulged to the general public. That's totally normal in an investigation. There may well be facts known already to the police and family which totally blow some of these halfbaked theories out of the water.
There is everything to be gained by raising the profile of Joanna Yeates; absolutely nothing to be gained by any of us speculating