"Why leftpondians call it a pound sign is just an indication of their strangeness."
Well, that bifurcation of language occurred because those on the right side of the pond entirely failed to properly document the shared language until the year after a tax protest spiraled out of control into treason, which out of desperate self-protection, turned into a revolution.
As in 1777, the language was finally documented, but those on the left side of the pond were embargoed and blockaded.
At least until a load of "wine" arrived from France - just in time, as the lefties were losing...