You can't police a billion people! Ethics and Morals are to the people, you can push them to some extent to stop doing things in public, kissing is okay, it's not objected in any western world either.
as parents, If you keep pushing your kids to stop doing certain things, they will find ways to do the same, no matter what. Too much of policing will lead to other subtle ways to do the same things. It's a free world, people can enjoy their rights and keep there ethics and morals to the mark, unless they don't care about the kids who will learn from observing.
Things are changing, and India is adapting most of the things from western world, and so is this.
