That's all probably true, except for those of us with ADD.
If I had to separate everything, I would never find them, nor would I have what I needed when I needed it.
I have to have everything together that I need. And as soon as I walk in the door I have to place it on the shelf inside the door that is there for the purpose: purse, little wallet (for work, it has to fit in my pocket), cell phone (that's where the charger is, too), and keys.
For years people have told me that the weight of having a relatively large set of hanging from your car ignition all the time can damage the ignition. Maybe so, but I just don't have that option. OTOH, my old crate had its 26th birthday and has never had ignition problems. Maybe the newer ones are more delicate.

And carrying your social security card is just begging for trouble. You only need it rarely, and should know when those times are. If anyplace (like Macy's) asks for it as a source of identification, shop elsewhere.
Sue