I spend a not-insignificant amount of time on the weekends making sure that I have all of the things I "need" with me in the right bag, depending on where I'm going. During the week, I have a backpack that carries the bulk of the burden, but on the weekends, if I'm going to a game store or some such, I may not want the whole backpack - I may just take a small shoulder bag. It always leaves me reconsidering exactly what I need to have on me in order to feel comfortable.
Most people have their own version of the daily "pocket litter" that they have with them every time they leave the house - keys, phone, wallet. But what kind of wallet? Is it all of the keys together, or separated by a valet ring? Is the phone in the wallet somehow? And what else do they feel like they can't leave the house without?
For example, my husband needs to have at least one pen on him before he goes anywhere. I need some form of reading, be it on my phone, my Kindle, or a physical book. My friend carries a notebook of ideas and a pen, just in case.
It's a definite way of giving a reader a sense of what a character considers important, if you show what the character carries with them at all times. Are they always armed? Do they keep pictures of family close at hand? Is there a lucky token of some sort that they would feel lost if they left it behind?
People can be strange and marvelous things, and it never hurts to find new ways of demonstrating insights into a character that the character may not even realize are there.