Political parties are in the business of garnering political
power and people join political parties because they want to
benefit from the political patronage that comes from being a
member. The more "useful" the member, the higher up the status
ladder he gets and the greater the patronage he receives. Political
parties themselves get support from powerful and rich patrons, eg.
businessmen, foreign powers, local notables etc. This kind of
support is a two-way street, you scratch my back, I scratch
yours.
Fortunately (or unfortunately depending on how you view things),
there is the problem of majority support. Just because the peasants
don't contribute as much as the big fishes doesn't mean they won't
go nuts and do something that while self-detrimental, may also be
extremely inconvenient. The examples of Indira and Rajiv
Ghandi's abrupt demise is a classic case of letting one's
political power cloud one's sense of mortality.
So the game of politics also involves "keeping up appearances"
and getting the "mandate of heaven". Of course, one can be a
bastard about it and make the citizentry dumb as apes or ship them
overseas on some suicidal expansionist crusade or terrorize the
masses with all sorts of made up bullshit and tax them blind but
like everything else in life, everything comes with its own set of
risks.
All political parties and systems function in the same way i.e.
like a big fat leech. The best you can get is if the guy on top
believes in practising somekind of egalitarian values out of the
enlightened understanding that man is ultimately a social creature
and that one shouldn't "shit where you eat" and so practices all
the machiavellian calculations out of a sense of
"neccessity".