Slavonic parishes, even in America, usually process for Corpus Christi. It is not unusual that the procession is longer than the Mass itself. It is a public witness that the Body of Christ is truly the Body of Christ. The Eucharistic Host, the Body of Christ, is placed in a monstrance (a special reliquary, with a luna [glass window]) and is solemnly marched. There are several stops outside and inside church, often with temporary altars. People sing Eucharistic songs and pray. At times the Monstrance is lifted for viewing and Gospel passages are read.
People within the neighborhood, but outside the faith are interested in this mysterious occurrence. It is not like other parades. It is noticeably solemn and mystical, and it cannot be confused as not being earnest and sincere.