[Kazamai]

Would it not be under the authority of a privately owned building to regulate their own Wi-Fi or radio signals?

For example, a movie theatre, airport or hospital could all have good reasons to block radio signals.

[jdbernard]

As I understand it, ownership of a space does not confer ownership of the radio spectrum, even within the confines of the space. They don't have the authority to regulate radio signals at all.