on יח עמוד א' the גמ says: היכי משכחת לה גבי כהנים
why is the גמ not concerned about ישראלים eating קדשים בטהרא (eg the קרבן פסח or בעלים eating שלמים)? do they not also have to eat with כלים טהרים?
[or is the answer exactly that - that we are not חושש for טומאת כלים which is מדרבנן by כלי אכילה - because we are more worried about the potential איסור כרת by someone who does not eat a קרבן פסח, or נותר by קרבנות?]
זלמן , Bet Shemesh
It may be possible to answer that our sugya is referring to the period after the destruction of the Beit Hamikdash when Yisraelim were no longer able to bring korbanot but the Tahara of the Parah Adumah provided by the Cohanim still existed. See Nidah 6b where Ulla said that the Chaverim in the Galil made pure wine and oil because the Beit Hamikdash may be built in their times (Rashi DH Chavraya). We learn that in the time of the Amoraim they practiced Taharah. To be able to do this, one must have Cohanim using the water of the Parah Adumah, so it may be that even though there were no korbanot at that time there were still Cohanim and Taharah.
Another possible answer:
It may also be possible to answer this question by saying that Tosfos learns like the Yeish Mefarshim in Rashi DH beVlad that the Braisa is referring to a vessel that became tamei on Yomtov. If it is needed for Yisraelim who eat kodashim beTahara then anyway it cannot be immersed on Yomtov since it could not be used on Yomtov since Kodashim requires He-erev Shemesh; it can only be used after dark on the day that it was immersed; and therefore one is not allowed on Yomtov to immerse a kli which could only be used after Yomtov.
KOL TUV
Dovid Bloom