I've noticed something quite similar in San Francisco - http://sf-planning.org/privately-owned-public-open-space-and-public-art-popos http://sf-planning.org/pri

I've noticed something quite similar in San Francisco - http://sf-planning.org/privately-owned-public-open-space-and-public-art-popos http://sf-planning.org/privately-owned-public-open-space-and... (most in SF seem to be clearly marked as private spaces for public use though)