There are tons of Santa Fe style homes here in the desert, and it's pretty standard - for whatever reason - to have a ladder perched against the chimney or an upper landing.
(I didn't see a seatbelt on it either!)
I am in Arizona, and every other house in the wealthier parts of town looks like that. I guess it is supposed to make it look like you and your Indian tribe are going to climb up and have a war dance on top of your version of Montezuma's Castle.
I've always disliked the "adobe fortress" style of architecture. We're building a house now that is totally contemporary. My wife and I agree, there will not be so much as a Navajo rug in it.
--ccm