I use shampoo ... whatever brand/type happens to be available ... for washing my hair, body, laundry, my bicycle, and sometimes even dishes. I don't see the point of carrying a whole bunch of different soaps. Once again, one item that has many uses.
And if we happen to be at a laundromat that has those little boxes of soap for sale, we might go that route ... or if we happen to be at a hostel or camp kitchen that has dish soap, we'll use that for dishes that day.