Funny, I don't really notice those burrito bar bags. I don't have one but people I ride with do and they are unobtrusive, imho.
I always have a seatpack on the road but I need more room than those tiny ones have. When we used to go into the mountains sometimes I would even wear a Camelbak for the water storage. I tried wearing it to carry a big jacket when it was cold but went back to stuffing the pockets with layers.