(Mishnah): On Shabbos, they performed the Aravah service in the same way that they performed it on a weekday, except that they would pick them before Shabbos and place them in golden barrels to prevent them from withering.

R. Yochanan ben Beroka: They would gather palm branches (rather than Aravah branches) and beat them on the Mizbeach.

That day (7th day of Sukos) was called 'The Day of Beating Branches'.

The adults would snatch the Lulavs and eat the Esrogs of the children.

(Gemara): This Mishnah only allows a child but not an adult to eat the Esrog.

Question: Did R. Avina not quote Rav as saying that an Esrog that became disqualified on the first day of Yom Tov may be eaten?

Answer (R. Yosa): In our Mishnah, this person can no longer use it (as he has already fulfilled his obligation), but others can use it, so it is still Muktzah (set aside for the Mitzvah); R. Avina was discussing a case when nobody can use it (as it has become disqualified, so it is no longer Muktzah).