I live in the USA. And I know about the use of ALL-CAPS.
Historical note: The use of ALL-CAPS as shouting is a veeeeeeery old thing, dating back to the early days of e-mail and Usenet (which were back then, for the most part, American), before the WWW existed, before forums existed. Today, ALL-CAPS is interpreted as shouting in e-mail, Usenet (newsgroups), chat, IM, forums, etc. This interpretation is not (and never was) specific to any country or region.
As for the rules, it may seem like a lot to get a page-full when you click on this forum's posting guidelines and then the general CD Freaks rules, but most of it is really just plain-old common sense, spelled out. The rules are not meant to be draconian, obscure, or counter-intuitive.
Okay, sorry for the off-topic post.