I'm a changer. I do have certain fobs that I use repeatedly on certain bags. Like on my black Tattoo Tote, I seem to always use the skull & crossbones fob. I don't know why, it just seems to go.
On my other bags, if I don't feel like changing bags that day, but I feel like some kind of change, I'll change up the fob I have on it. I used to use scarves, but I got tired of them very quickly as (for me) they get dirty and/or come untied.