It’s not unusual for Japanese companies to have shrines on the company’s grounds. I guess this one is on the roof because there’s not enough space anywhere else.
Long-time resident in Japan (since 1993) but originally from Canada. Has written guidebook chapters, magazine articles, tons of blog entries and even a book about less-known aspects of Japan. In his free time, he loves photography, cycling, and exploring interesting and obscure places around the Kansai area.