Before R' Aron Teitelbaum became Monroe Satmar Rebbe, he was the Rosh Yeshivah of Satmar Yeshivah in Monroe.
At the time, there were no "Hadlakas" Bon-Fires in Satmar on Lag Be'Omer because they didn't have that "mesorah."
Satmar boys, like all boys, need entertainment, so they ran to other Rebbes to witness and to celebrate Lag Be'omer, celebrations that had huge "hadlakas," some ran to Chabad where Lag Be'Omer is a huge day and some even ran to Meron in Israel.
This did not fair well with the Rosh Yeshivah, because he was frightened that the boys would find other Chassidic sects desirable, and would leave Satmar altogether.
So one year the then Rosh Yeshivah, R' Aron Teitelbaum, decided to gather all the boys a couple of weeks prior to Lag Be'Omer for an "asifah" to warn and threaten any boy that went to any Lag Be'omer celebrations with expulsion ... כדרכו בקודש!
His reasoning at the "asifah" was two-fold ....
Number one, this wasn't a "mesorah" in Satmar.....
and number two .... Lag Ba'omer is not a "Chutz Le'aaretz Yom Tov;" its an exclusive "Israeli Yom Tov" because Eretz Yisroel does not have two days of Yom Tov, he reasoned, .... the gedoilim of Eretz Yisroel must have found it proper to make an additional Yom Tov called "Lag Be'Omer!"
A Buba Mieseh!
When he became Rebbe ... he changed his tune.....
His gaboim, in a panic, were telling him that the majority of his chassidim are leaving Monroe on Lag Be'Omer to celebrate ...... yes..... the New Israeli Holiday!
Instead of making an "asifah" to explain the new Satmar minhag of making a huge Bon-Fire on Lag Be'Omer, which everyone would understand, he remained quiet, hoping that no one would remember that he barked against this not too long ago!
His brother, R' Zalman Leib, Satmar Rebbe of Williamsburg doesn't practice this new Satmar custom and does not make an hadlaka ...
I guess he isn't frightened that his chasidim after having celebrated an hadlaka with some other rebbeleh would leave him!