A complimentary place is paid for somewhere, usually within the price the other pilgrims pay, so the details deserve plain questions. Which expenses are covered: airfare, a single room, gratuities, meals outside the program? Who bears the shortfall if the group turns out small? Does the arrangement fit the policies of the parish or diocese? The custom presumes one priest traveling with a lay group; a group with several priests, such as a seminary group, needs its own written arrangement.
The priest travels as chaplain, not as organizer or salesman. He celebrates Mass, hears confessions, and leads the group's prayer, and he carries his celebret, the letter of introduction from his bishop or religious superior that canon law provides for a priest celebrating away from home. Shrines want to know who he is: the Shrine of Fátima asks the organizer to give the name of the accompanying priest when registering a group.
On a Bold Pilgrim pilgrimage the same model applies. The priest's place is complimentary once enrollment reaches the threshold written into that pilgrimage's offer; for planning, that is about 10 to 15 paying pilgrims in a small group and more in a coach group. If enrollment falls short, the difference is never quietly added to the other pilgrims' prices; the offer says who covers it. Where a pilgrimage has a lay host as well as a priest, both travel on the same terms. The priest does not sell the trip and receives no commission.