When I'm running errands, I put my wallet & cell phone in my pockets and take my car keys.
If I take my purse (really a small backpack) it's somewhat more, but considerably pared down from what I used to haul around. It includes (but is not limited to) a small notebook, a small pack of tissues, a couple pens, my quild membership card, a small bottle of sanitizer, some lip gloss, eye drops (I have dry eyes), a nail clipper, a small tape measure, some photos of the grandkids (never know when I'll have to brag a bit!). At any rate, it's a lot smaller -- and I suspect lighter -- than a lot of bags I see around.
Julia > I have just weighed my handbag (purse). It weighs 2.5kg/5-6lbs