I'm unsure why we need one. The only use I see for it is to prevent people from seeing your code and editing it. However, I would *never* want to run someone else's script if I couldn't look it over and make sure there aren't any back doors or other malicious code in it. Scripting such things is REALLY easy and if you can compile it so that no one can verify if it's a safe script, then I see that as a really bad thing.
If someone wants to write a utility to run OUTSIDE of mIRC without mIRC running, then compiled could be useful. However, if you really want to do that, you're much better off learning a real programming language instead (C++/VB/etc).