If we take the collectivist fallacy to mean that society as a whole does not pursue an end, then it has some appeal. Society is not a substance per se and does not have the same sort of natural teleology that, for example, animals do. It is even appealing to see that men seek their own ends in society and they don’t explicitly and immediate act for the common good of society.
However, when we apply the collectivist fallacy to a family it becomes less convincing. A family is essentially a small society or collection of individuals. Yet, it is manifest that the best and healthiest families are those that seek the common good of the family as a whole. If each individual merely sought there own ends the cohesiveness of the family would dissolve. A family cannot be reduced to a collection of individuals making merely self interested exchanges with no concern for the family as a whole.
In a similar way, the cohesiveness of society could not be maintained were the common good of society wholly ignored. It might not be that every individual actively, explicitly and immediately seeks the common good of the whole of society, but they do and often merely in the general course of the day. This is in fact necessary with a highly advanced and complex society as the modern nation state.