You can no more, with integrity, play fast and loose with communities of faith than you can with families or with lovers. So we have unfaithfulness both amongst people who have turned away of God, and amongst others who still look to God but act as individuals without regard for membership in the body. A true member of the body can never presume to judge other Christians. Many are attracted to the excitement and authoritarianism of the more conservative streams of Christianity. One of the ironies of the present fashion for shopping around is that it tends to sectarianism.
People become selective and critical of the differences.
The breakdown of denominational loyalties often ends up in blind defensive attitudes as small entrepreneurial sects seek members at the expense of the older more established churches. The unworldly are sometimes fashionable and even worldly in these attitudes of the competitive consumer society which they use to their own advantage. Sectarianism, in which people separate themselves in a defensive, judgmental and critical way from other Christians is worse. But I also believe there are good reasons to belong where we do and that the differences that divide Christians will never be overcome by careless disregard for our traditions. To act with contempt for serious differences between Christian traditions is to take far too lightly the conscientious commitments of other Christians and the generations of believers who have handed on the faith to us.