Q. How is it that some rabbinically qualified people take on jobs outside the rabbinate?
A. This was always the case. Because of the principle, “Do not make the Torah a spade to dig with” (Avot 4:5), Talmudic rabbis practised a variety of professions; one was even a gladiator. The concept of the rabbi was quite different from the modern idea of a congregational minister. The rabbi was no more (or less) than a learned layman. Certain professions became particularly common among rabbis, especially medicine.
The modern spread of yeshivah learning has created thousands of rabbis who work in industry, commerce and the professions. Indeed, when the Lubliner Rav, a great rosh yeshivah, was asked where he was going to find congregational posts for his 300 students, he said he expected only one would be a community rabbi but hoped the other 299 would be learned enough to appreciate their congregational colleague. Rabbis who work in other areas ought to be able to exert a subliminal spiritual and ethical influence and to raise the quality of society from within.
Whatever the profession he chooses, a rabbi must always ensure he is a role model of morality and decency.