The love of money, to the exclusion of all else, is the root of all evil.
I only have experience with my LUG, Phoenix Linux User Group (http://plug.phoenix.az.us
) so my thought may be off base.
Our LUG has no dues or fees of any kind. There is no tresurer or tresury. We meet at locations that people provide to us. We do activities that someone is willing to pay for or where each participant brings their own or to share. No money changes hands for anything except if you get a distro from someone and have no blank CDs to give in exchange. And then, it is a transaction between the people involved, not the group. Without money, a great deal of the "greed incentive" goes away. Only those willing to work or at least carry themselves will be there.
Maybe our group has been lucky that no one has become power hungry. Maybe the lack of monetary control keeps the power hungry people away.
That would be the single biggest tip I could provide for keeping a LUG together.
Of course, I don't know if money led to the problems with the LUGs you cite. Tell us more about it.