The point is, the more AI's you fight, the more you will develop your own strategies and tactics against them.
Unfortunately, players may easily exploit this sort of strategy against players; they're dynamic, compared to the "difficult" AIs who just rush towards you, which are usually stuck with limited options.
For example, do you think a player who just plays against AI's (you may want to add 'skillfully' if you want) in GG or SC will simply win against somebody who has skillfully played and won against a lot of people in tourneys? It applies to gaming in general.
