It's a mechanism by which the CIA(or others!) could pay operatives covertly.
I'm pretty sure i read this like a decade ago, but to me it makes sense. Especially given that numbers stations apparently blared out orders into the late 1900s.
When HTML is rendered, multiple normal white space characters collapse into one, e.g. if you write "<p>Hello it's me</p>" it will be displayed in a browser as "Hello it's me". The source code tells the whole truth.
https://web.archive.org/web/20140403012916/http://www.finney...