How widely do you think that Hindus accept their ritual without belief as Hinduism?
Very widely indeed, because it would be a major faux pas for one Hindu to ask a another "Do you really believe in all this? Say you do!" Instead, people are not asked about what they feel deep inside, so they are free to believe whatever they wish. This is what makes Hinduism so inclusive and, over time, so syncretic.
Hindu fundamentalists vs. Hinduism: Column [usatoday.com]
Being very familiar with the contemporary Hindutva phenomenon because I work in a field affected by it, I very strongly suspect that the amount of Hindus who do not believe in the supernatural is greater than the number of Karnataka-state demagogues and their followings. These sorts aren't quite at the microscopic level of a Westboro Baptist Church, but considering the population of India, they might as well be, they've simply learned to work the media and engage in some minor vandalism like similar groups abroad.