The last Mishna in Kiddushin discusses the pros and cons of various occupations and the tendencies of those who engage in them. The Mishna discourages a variety of occupations because it is almost inevitable that one who engages in them will steal from others at some point. Then, regarding butchers, the Mishna states: The most kosher of butchers is the partner of Amalek.
The commentators struggle to explain this comparison. We can easily understand that butchers are challenged with the opportunity and temptation to cheat their customers in a variety of ways. But the partner of Amalek? The arch-enemy of God and the Jewish people? Why is the butcher singled out in this way?
We know that the calling card of Amalek is safek, introducing doubt into people's minds about accepted truths, universal morals, and timeless traditions (see my previous articles on this subject). By undermining truth by undermining the notion that there is even such a thing as objective truth Amalek wages war on God, whose seal is emes and whose Torah is divine, unchanging Truth.
The manner in which a butcher steals is different from the others listed in the Mishna. A shepherd, for example, typically steals by allowing his flock to graze on private property. A storekeeper typically steals with false weights and measures. They and others who cheat people or damage their property are likened to listim, bandits who rob people in the course of their travels.
The butcher's weak spot is different. His main temptation is when an animal he slaughtered might be treif but maybe not. The laws in this area are extremely intricate, and the slightest nuance can be the difference between a kosher animal and a major financial loss. Does that spot on the lung render the entire animal treif or is it nothing? Did the butcher tilt his hand ever so slightly when slaughtering the animal, or pause for just a moment? Was the knife sharp enough?
We know all too well that many butchers have fallen prey to temptation in this area, and no amount of supervision can completely prevent opportunities for fraud. Even the most kosher butcher will find himself in situations of doubt situations that he can cover up and the temptation to do so will be powerful.
Amalek will whisper in his ear that it's probably fine, the rabbis are too strict anyway, and no one will ever know. It isn't worth throwing out thousands of dollars worth of meat, angering his employer or his client, suffering a huge financial loss or causing it to others, possibly even creating a meat shortage for the entire community over something trivial.
It's fine, says Amalek. It's not really treif. There is no reason to be stringent. Don't even raise the issue and create a whole fuss over nothing. You know better.
It is for this reason that the Mishna describes the butcher, more than anyone else, as the partner of Amalek.
[When I first wrote this I was dismayed that none of the commentators I saw offered this explanation, which seems straightforward. My brother later found that the Ri from Lunel in fact explained that the butcher is likened to Amalek because he feeds the Jews safek treifos surely due to the nature of Amalek as noted.]