Many hard core libertarians are never seen by the Libertarian Party because they have no belief in politics. FIFE is beyond politics, it is culture. People who despise all things political can wear a feather and go to FIFE meetings expecting to find some agreement. People who just want to be left alone can wear a feather. The loose party atmosphere is intended to encourage lots of individual conversations.
People generally like to eat and drink and talk.
If the regulars bring drinks and snacks and others can be convinced to contribute to a kitty it need not be expensive. I try to have as much literature out as there is room for. Literature from all different groups is available to best match the interests of the partiers. The hardest part is encouraging the emergence of leadership from chaos. There have been successes with this method but the results are generally disappointing.