I don't now if anyone else has noticed this, but this is something I've frequently observed over the time of my ministry.
In churches where the minister / priest / pastor wears liturgical robes (alb / cassock and surplice / chasuble / etc.) during the worship service, the other members of the congregation wear a wide range of clothing during the service, based on their own preferences.
In churches where the minister / pastor wears academic-style or legal style robes during the worship service, the other members of the congregation are far more apt to wear business-style clothing during the service, even if they don't wear business-style clothing at any other time in a normal week.
In churches where the minister / pastor doesn't wear any robes during the service, many members of the congregation tend to copy the pastor's clothing style.
Has anyone else noticed this?