i wonder if those who do not actually rinse use the two sink method much like many pubs do with glasses?
that is, the dirty glasses (or dishes) are scrubbed in soapy water in one sink, then are dipped into a second sink of clean (or rather un-soapy) water before being dried.
like luvs mentioned, ingesting soap is like taking laxatives, so i can't imagine not rinsing or at least dipping in clean water.
even with the second sink method though, you have to figure that the cleanliness of the un-soapy water would be increasingly adulterated as each dish is introduced, depending on the volume of both water and dishes.
in nomine patri, et fili, et spiritus sancti.
Meh nom eh noh...doot dooooo do do do.