Classifying Hinduism and Buddhism as "religions" in the Western sense of the word is imprecise and misleading at best.

You can be a Hindu atheist: https://en.wikipedia.org/wiki/Charvaka

Swami Vivekananda popularized the Ramakrishna school of thought, but they themselves deny to be called Hindus.

Goa deputy Chief Minister considers himself to be a "Christian Hindu": http://www.firstpost.com/politics/india-hindu-nation-im-chri...

Hinduism in not an organized religion like Abrahamic religions. The definition of Hinduism is very fluid in practice.

Similarly one can be a Buddhist atheist as well.

PS: Also please add Sikhism and Jainism to the poll -- two other major Indian religions!