Japanese wedding customs fall into two categories: traditional Shinto ceremonies, and modern Western-style weddings.
Most couples choose their wedding style, not for any religious reason, but rather as a fashion statement. A Shinto wedding focuses on ritual practices, carried out diligently, which establish a connection between present-day Japan and its ancient past.
The wedding itself, and the lavish reception that follows the ceremony, has no bearing whatsoever on the couple’s legal status as husband and wife.
It only becomes legal once the marriage notice (konin todoke) is submitted and registered.