Why do people say "piped-in music"? Also "pumps".

Or maybe I should rephrase it, why DID people say “piped-in music”? It’s sort of an old expression which you don’t hear much anymore, but it doesn’t seem to make much sense. If you have wires leading to speakers, those wires do carry the current in a manner analogous to how a pipe carries water. But for everyday conversation, that’s a rather stretched analogy, especially since wires don’t have a hollow interior that conducts the thing being conducted.

Nowadays, if you have live music, it’s considered ideal to have the musicians in the same room with you. But was there ever a time, before the advent of recorded music, when people loved music but despised musicians? So much so that, rather than being in the same room with them, they would have the performers doing their thing in a different room, and have their output “piped” through an audio conduit to where your guests were?

And on a different note, are women’s “pump” shoes so called due to resembling an old fashioned pump handle?

Not speaking from any position of authority here, but “pumps” is sometimes used in England to refer to sneakers. Dictionary.com gives us the possible etymology of “Probably so called as being worn for pomp or ornament”. Futhermore, where I would say ‘cable TV’, a lot of Irish people say ‘piped TV’.