While the picture might portray a different reality to the unknowing observer the gold medal doesn't belong to me. I did nothing to earn it and even though I wore it briefly, that didn't make me an Olympian.
Genuine faith is the same way. We can call ourselves faithful because of our family heritage or our regular church attendance, but without personal experience it doesn't mean much. It's not genuine to say we have faith because our grandmother did or because we never missed a Sunday service. Faith only becomes our own when we put the effort in to battle through understanding and real life application.
Without individual investment we're just wearing what someone else has earned.