Once upon a loooong time ago and in the time of VMS and e-mail readers 'pine' and 'tar' (IIRC) these programs allowed you to keep a file of data to be appended to each post. They became "geek boxes" of tersly coded personal information significant to no one excepth the guy in the next cubicle. Now even OE allows a "signature."
The conspiracy of ignorance masquerades as common sense.