All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad is His slave and Messenger.
There is no doubt that this act is a religious innovation, and the people of your village have to repent from it and stop doing it. You have to clarify to them in a wise and gentle manner that this act is not reported in the Sunnah of the Prophet and that no one among the Salaf (righteous predecessors) did it, as all the good is in following them. If this act had been good, then they would have preceded us to doing it.
If they are not convinced, then you are not sinful for what they do, as you advised them as required of you. But do not participate with them in their religious innovation, and do not be embarrassed by that as you are on the truth that is in conformity with the Sunnah of the Prophet .
Allah knows best.