Green, Yellow, or Blue tip Ladders?

I have seen green tip ladders on the roof racks of some well known and prominent window cleaning companies. Sometimes in person here in the Boston area and sometimes on the internet. Two have served on the IWCA BOD. So that got me thinking. Why are so many window cleaners hauling heavy blue tip ladders around?

At the ripe old age of 58 I always think lighter is better. Of course I grew up building tree forts in the woods that were 20 feet up, so it takes more than a little movement in a ladder to scare me. The green tip ladder is rated at 225lbs and I weigh 210lbs so I would be SAFE on that ladder even if the ladder moved a little, right?