Prayer Lists

Across the Christian world there are ongoing prayer lists within church bulletins and Sunday School classes.
While some ask for prayer for anything and everything (i.e. their third cousin’s hangnail to be healed), others never ask for prayer nor really want others to know much about their personal life. I’m convinced that I belong to the latter group.
And what happens if God does not answer prayers in the way that we would prefer? Would it be best not even to ask at all, rather than become discouraged?
I’m also convinced that some prayer lists are just vessels for gossip. Person A has a life threatening disease? Automatically put it on your public prayer list, whether or not the person affected by it asked for it to be made public. Someone is sinning? Put it on the prayer list. Others have felt the same way.
Meanwhile some people thrive on seeing human trainwrecks, one reason why shows like Intervention remains popular. Maybe its an effort to feel better about ourselves once we see the poor condition of others. Maybe it feels good to pray for someone in worse condition than oneself.