Most people who play or are involved in music have hearing damage, so it's not guaranteed that a conductor would be able to hear the difference. Also, the connectors that are silver are nickel plated.
It's nice to have a continuous run from amp to speaker but it's not always easy to deal with the extra cabling and for cleaning/painting a room, having a wall plate with inserts makes life much easier. If everything is clean and tight, it shouldn't make any audible difference.