The only time that it may be a problem is if you decide to get married, have your children baptized, or have to make funeral arrangements. One of my friends goes to one parish and has never stepped foot in his home parish. He’s not registered at either. He approached the Pastor of the parish he attends for marriage counseling and the Pastor told him that there was no registration on record for him. When my friend explained the situation to the Pastor, he was told to ask his home parish Pastor for a letter giving him permission to seek marriage counseling with him as a sign of respect and courtesy to the home parish (his home parish Pastor wrote the letter immediately).
It’s also happened with funerals in the area too.
Some dioceses don’t really pay attention to the boundary thing. Mine does, so that’s why I try to tell people about it.
There is also the issue of “personal parishes” - parishes established by the bishop for persons of some particular group.
Examples include a parish for the Hispanic community in an otherwise non-hispanic area, or for Poles, or persons of a different church sui iuris under the bishop’s care (usually, in the US, these are in separate overlapping dioceses, often called eparchies).
In Anchorage, for example…
Our Lady of Guadalupe is a non-territorial parish. It was erected specifically for the Hispanic Community. Anyone of hispanic descent can, by registering there, be properly cared for by the pastor without reference to the territorial pastor.
Holy Family Cathedral is also designated as a personal parish… for any Catholic of the Roman Church who wishes to enroll there. There are parishioners who drive 80 miles to attend there, as for one reason or another, they don’t want to be enrolled at their local parish. It also used to be the Filipino personal parish, with a Tagalog mass every other week.
St Anthony hosts a quasi-parish for the Korean Community as a personal parish. They have mass in Korean, and all who speak Korean are eligible to register there.
St Nicholas of Myra is dually constituted; it’s a parish of the Eparchy of Holy Protection of Mary of Phoenix, and thus a Ruthenian Parish. It is the territorial parish of all Ruthenians in Alaska. By tradition, since there is no Ukrainian parish, it also is the territorial parish of the Ukrainian Church Catholics in Alaska. It also is constituted as a personal parish for Roman Catholics attracted to the Byzantine Rite, so they may elect to enroll there. Further, by agreement between the eparchy and the Archdiocese, it’s also ascribed the canonical care of all members of other churches in union, even tho’ non-byzantines would canonically fall to the local territorial bishop of the dominant rite.
In dioceses with large urban areas with diverse and scattered ethnic groups, such non-territorial (Such as OLoG or Holy Family Cathedral in Anchorage) or semi-territorial (Such as St Anthony in Anchorage) parishes allow for retaining that social and ethnic connection that the old system of ethnic neghborhoods and ghettos used to enforce… without the ghetto.
Many dioceses simply give up, and allow choice of parish in general, as it reduces confusion.