This is not the same thing. Many (MANY) people are not tech savvy enough to know what PhotoStream is, what it does, to say nothing of whether it's turned on or not. The analogy would be more apt if the maid takes the key, copies it, and puts the copy outside under the doormat without telling you.
My work colleague does medical examiner work sometimes (we are MD's), which requires him to photograph bodies. Often very gruesome scenes. At his kid's birthday party, they had an AppleTV hooked up. He activated PhotoStream on the AppleTV with the intent of sending photos from the birthday party from his iPhone to the big screen. You can guess what happened. The wife was REALLY mad at him. But he didn't know the photos were being uploaded. He's an extremely intelligent person but he knows nothing about how tech works. Don't equate tech illiteracy with intelligence. It's not the same thing.
You guys need to remember that what's obvious to us tech geeks is NOT obvious to the rest of the world. And technology needs to be designed for people who DON'T know what they're doing. Photos (and documents for that matter) should never be automatically uploaded unless the user specifically asks to do so. THEN, if they got stolen, it would be more similar to the "key under the doormat" analogy.