I'm also wondering... To my knowledge, a human player can't get another MGL if he hasn't used a first one yet (for SGLs it's OK). Am I wrong ? That means that the AI cheats : it can get useless MGLs without using them for armies !!!
The AI cheats but doesn't know how to get advantage of it, ROTFL.
Question : in C3C 1.22, the AI NEVER NEVER NEVER builds an army, is that true ? But it can sometimes attack yours if enough conditions are there, it happened to me in my 1st game vs Stapel (that was the Germans), this I know.
In RoR in solo, the AI can fill its initial army. As Rome, I saw a Carthage AI come with a badly filled army, that I immediately managed to destroy. The army came from Carthage to Sicily IIRC.