It could be a social embarrassment factor. Wanting to fit in to the crowd. This isn’t any kind of unforgivable sin, but it omits something that would make the worship more enveloping. It serves as a reminder that later, the right thing to do with those hands is to offer their service to the Lord in any circumstance.
Like the First Pope: Peter??
Galatians 2:11-12
11 When Cephas came to Antioch, however, I opposed him to his face, because he stood to be condemned. 12 For before certain men came from James, he used to eat with the Gentiles. But when they arrived, he began to draw back and separate himself, for fear of those in the circumcision group.