The importance of trading in Catan

So, I was thinking about my ridiculous 2:1 win/loss ratio in computer Catan, and I realized something crucial. The AIs don't trade. Oh, they'll trade with me when I ask for it on my turn, and I see messages about their using 4:1 trade or ports. But I never *get* trade requests and I don't think they're secretly trading with each other. That's why the games end in 15 minutes; they're not just faster decision-makers, they're skipping a key part of the game, and not benefitting from trade when it would be most useful to them.

So much for having evidence that I'm an awesome Catan player.