The law that limits ritual defilement of food only to something that has become wet due to one of seven liquids (Vayikra 11:38) which prepare the animal for possible defilement:
- wine
- blood
- oil
- dew
- honey
- water
The rabbis argue that there is no relevance if ordinary meat is touched by unwashed hands. The mishna cannot be discussing kodashim, sanctified meat, since it specifically enumerates bird and wild animals which cannot be sacrificed. One comment teaches that the case of the Mishna is chullin she-na'asu al taharat hakodesh, ordinary meat that is treated as if it is sanctified meat. In that case, defilement from unwashed hands is significant.
Steinsaltz notes that in the times of the Temple, people kept the laws around ritual defilement even when eating ordinary food so that the would not make mistakes when they ate sanctified food. Rashi taught that this practice was common to kohanim or Jerusalem residents because they were used to eating sanctified food. The Meiri adds those people who were in constant contact with such food like merchants who supplied the Temple with wine and flour and oil. People continued this practice after the destruction of the Temple hoping that the Temple would be rebuilt and the laws would be in practice again.