Can you provide a source that says that the SLC community was upset over the polygraphs? As I remember, Tom and Ed Smart had polygraphs done, as did a few other members of the Smart family.
I'm not quite sure what tip you are referring to, but the police are not involved in the search anymore. The tips come into the Elizabeth search center, and the family decides where to search next. This weekend they are asking hunters to be on the lookout. And I'm sure the networks ratings have something to do with why they keep interviewing the Smarts. Face it, this is a true mystery, and it gets ratings. Otherwise, the networks and cable shows wouldn't give the Smarts the time of day.
And if I were in the Smarts shoes, I would do the same thing. If the media is going to come calling, then by darn, I'd keep Elizabeth's story in front of them. As far as caring for the thousands of other missing children, well, what else can the Smarts do? They are helping in the Amber alert becoming nationwide, because of Elizabeth's abduction (and I believe it brought high ratings to the TV networks), anyway, many missing childrens faces and names were on newscasts for many weeks, because of the heightened awareness other abductors of children were found this summer. And no, I am not giving the Smarts all the credit, but they are doing something. It is really hard to help the thousands, it is much more human to want to help the one who is lost that you know (metaphorically speaking.)