In many regions people eat only with their right hand and it is considered impolite to extend your left when shaking hands. The idea is that your right hand is the cleanest. I have known this for a long time and always assumed that the people that practice this were trained at a young age to wipe their ass using the left hand. I may have had this wrong.
A man we met in Hampi shared, "Everyone is aware we all use our right hand to clean after making toilet, it's just that we all make sure that hand gets more clean."
On that subject, I am really loving the spray hose and find it to be a much more efficient way of getting the dirty work done than with the toilet paper method. I'm feeling fresher than ever in such a muggy place. Thinking of installing one when I get home.
Another side note: I'm amazed at how well the Indian folk eat a full meal without tools and just one hand. I made a complete mess of my self using both hands and ended up doing extra laundry after trying the mono-hand method.