Building a wall is akin to limiting the site only to registered users. They don't do this because they want google to index them, but it indexes only publicly a

Building a wall is akin to limiting the site only to registered users. They don't do this because they want google to index them, but it indexes only publicly available sites. I.e. that's ok to build a wall, but it's not ok not to build the wall but sue some people among the ones who take a look at the house.