The reason of this popularity lies in the Shinto religion, where vermilion is the color which expels evil and diseases. That's why the Shinto torii are often painted in this shade and in some cases entire architectural complexes, like the one in the photo, are colored vermilion...
EXIF info:
Nikon D700
Lens: 24-70mm F/2.8G
Focal Length: 31mm
Aperture: F/5
Shutter Speed: 1/400s
ISO Sensitivity: ISO 1250