The Korban Olah is completely burnt on the mizbei’ach with nothing remaining for the kohanim. Horav Chaim Volozhin, z.l., suggests that this is essentially the reason that korabanos akum, sacrifices offered by gentiles, are considered olos. The gentile is not inclined to share any part of his sacrifice with the kohen.
Rav Chaim applied this logic as a response to those malcontents who were disturbed by the fact that the meshulachim, tzeddakah collectors who canvassed communities on behalf of the Volozhin Yeshiva, received their salary by taking a small percentage of the contributions for themselves. He stated emphatically that such criticism was not Torah-oriented. His proof derived from the fact that gentile sacrifices were deemed olos and not shelamim, peace offerings. Why is this ? It is because the gentile “cannot” permit the kohen to receive his due from the Korban Shelamim. It bothers him that when he offers up a sacrifice to the Supreme Ruler of the world the kohen should partake thereof. Consequently, those gentiles who were inspired to offer korbanos would like to see the entire korban burnt, as a total sacrifice to Hashem, with no mortal sharing in it. “Not so,” says Rav Chaim, “are the sons of Avraham, Yitzchak, and Yaakov. On the contrary, it gives us our greatest sense of satisfaction when we see a kohen eating from the Korban Shelamim. A Jew who is petty and does not “fargin,” tolerate, the fact that another Jew has parnassah, a livelihood, is acting in a manner totally alien to Jewish character.