When you make an offering of meika, you'll be rewarded in proportion to the amount that you donate. Once you've confirmed the amount of meika you wish to offer, you'll then choose a prayer to complete the process.
When you make total offerings worth 10,000 Meika in these boxes then you will unlock the "Pious" achievement / trophy.
Offering Box (Chishima Shrine)Offering Box (Hitani Shrine)Offering Box (Kamio Shrine)Offering Box (Kirigaoka Shrine)Offering Box (Namihara Shrine)Offering Box (Onten Shrine #1)Offering Box (Onten Shrine #2)Offering Box (Onten Shrine #3)Offering Box (Onten Shrine #4)Offering Box (Sekano Shrine)Offering Box (Shimokusa Shrine)Offering Box (Shiratsuki Shrine)Offering Box (Shiroyama Shrine)Offering Box (Tatsui Shrine)Offering Box (Toyoi Shrine)