Longbow:
Not only, as previously noted, are EAA guns made by an Italian firm, the guns are subtly different -- not truly CLONES in the common sense of the word. (They're made on the same basic pattern, but a lot of minor differences.)
The EAA guns are simpler (arguably better, in that respect), and have incorporated design features to make manufacturer easier, too.
Many parts don't interchange (different size pins, for example). Barrels aren't interchangeable, mag releases are different, safeties are different, firing pin and pin safeties are different, slide don't interchange, etc., etc. Even mags can cause problems, as the mag releases are set in subtly different positions. (The mags can be made to work with a needle file, if they have problems.)
There's nothing wrong with EAA guns, per se -- and lots more after-market parts are available for them. I have CZs, an EAA, and other "clones," including a couple made in Switzerland, and like them all.