First off, those little strings dig into shoulders if you are carrying anything heavier than a feather in them. Also, you get what you pay for, so if you pay $4 for a bag, don't be surprised when the strings shred, or come untied, or something else.
My DH usually wears cargo shorts and can put a poncho (cheap dollar store one) in a pocket, and a bottle of water in another pocket. He never carries a bag.
I carry a cross body bag that I wear around my waist like a fanny pack (but looks better!). I don't like straps on my shoulders or a strap cutting my chest in half.