Why Indians worship many Gods?

Met a friend's mother on the weekend. She had returned from Singapore after staying with her elder Son. Following is a small incident she narrated.

Their Christian housemaid was amused to see her worship photos of different Gods.

maid: There is only one God. Why do you worship so many Gods?
She: We could just boil rice and eat. But still we make steamed rice, jeera rice, pulav, khichadi and so on....Its about different forms. God is just one!