A parishioner, wherever he/she may die, has the right to be buried in the churchyard, or other burial ground, of his/her own parish.
So they were probably buried in the Grave Yard of St. Michael's Church, but before 1880 no body could be buried in consecrated ground except with the service of the Church, which the incumbent of the parish or a person authorized by him was bound to perform. This caused a grievance with non-conformist ministers, which was removed by the 1880 Burial Laws Amendment Act which allowed the bodies of persons entitled to be buried in parochial burial grounds, whether churchyards or graveyards, to be buried there without the performance of the service of the Church of England.
Stan