I saw this movie and was interested at the tech that climb the telephone pool to hookup the transmitter.

Was this a common thing back in the day? Did random poles have equipment that non-telephone company people could hook into for remote use like this? I can think of many different use cases for this in the days before widespread mobile telephones.

I'm pretty familiar with telephone history and technology but can't seem to find references to these or what they where called. Anyone have any pointers?