Colloquially they are called “3-Day Jews”, a phrase originating in the Biblical law that required a pilgrimage to the Temple for Pesach, Shavu’ot and Sukkot.
Today’s 3-Day Jews tend to ignore these three festivals, with the possible exception of Seder night, but go for the first day of Rosh HaShanah and for Yom Kippur, which makes them 2-Day and not 3-Day Jews.
The question is how a faithful follower of the whole year is meant to feel when there is a sudden invasion of your sacred space on the High Holydays.
Do you react as a cynic or with indignation? Do you gravely doubt whether it really is spiritual yearnings that bring the crowds to the services?
You might be right, but you should never discount the pintele yid, the latent spark that hides inside every fellow Jew and tells them it’s time to be with their people, language, melodies, ambiance and rituals.
Many will merely pay lip service and vanish for another twelve months, but others will find themselves changed.
The Ba’al Shem Tov told about a shepherd boy who came to the synagogue on Yom Kippur but knew no Hebrew prayers. He fiddled with something in his pocket until finally he drew it out. It was a whistle, and he blew it in the crowded synagogue.
The congregation were aghast; the Besht said that something had entered the boy’s soul and he had to respond.