Hundreds of millions of Indians have indoor plumbing/toilets. Do you honestly think that all of the millions of people that live in high rise apartments in Mumbai, Kalkota, New Delhi, Hyderabad, etc; all go in the streets?
"Oh Patels, thanks so much for coming to our house warming party. Let's not use our toilet here, but let's all go down stairs and defecate at the bus stop. Good times!!!"
It is true that India is a developing country that is improving its sanitation. The Modi government is in the middle of a project to build millions of toilets through out the country, and to change the rural/poor culture in that regard.