According to the Sages there is a tradition that a person should sooner hire himself out to for idol worship (avodah zara) than accept charity from others. The Sages comment that this maxim was misunderstood by Rabbi Yehonatan, for its true intent was that a person should accept work that is not what he ordinarily does (avodah she-zara lo) rather than accept charity. To support this interpretation, the Gemara relates something that Rav once said to Rav Kahane - you should be willing to skin animals in the marketplace and get paid, and you should not say that it is below the dignity of an important person such as yourself.
The Rashbam explains that there is no embarrassment involved in working for a living, so there is no hillul ha-Shem for a scholar to work, even in tasks that appear to be demeaning.