That's not hacking, its just equipment. Regen-stacking is a well known strategy, and what with the AI's large amount of funds, its even easier for them.
That's how they make AI harder. They arent smarter, they just have more money, favor, and experience.
However, I've yet to be defeated by nightmare AI on anything less than 3v1, and I'm just an average player. I don't care how they make them tougher, because A: They're STILL pushovers, and B: I don't play AIs for fun.
Lastly, you're saying this because of 1 single game, and you're saying your AI did not do the same thing. Just think about that.