Hi Mark...
Good questions!!

rops:
There are spokespersons for certain rinseless/no rinse products that have stated you can actually use them
all by themselves...
instead of using car-wash shampoos...in/for a traditional car-washing session.
Along with this above stated
"feature"...it's also been stated that:
-You won't get the same amount (if any) "suds"/foaming with this method.
-This method will:
"do the job just fine"...
-"Whether you rinse it or not".
It has been duly noted that most car-wash shampoos have some level of lubricity;
and, by: adding a little bit [1/2-1.0 oz or so (?)] of some rinseless/no-rinse products will add some more lubricity...
as well as "soften" the wash/rinse waters.
The price-points, per use, of a rinseless/no-rinse product versus those of dedicated car-wash shampoos
may become the determinate factors in selecting one type of car-wash product/method over the other.
(I will add that water restrictions/availability should be listed as a concern for some folks)
A FUNX725 Editorial:
-I have yet to personally do a comparison of either the costs, cleaning abilities, and/or lubricity differentials.
But it seems, to me, that a person would have a whole
bucket-full of "no-sudsing lubricity-agents" when using
only a rinseless/no-rinse product in/for a traditional car-wash session.
However, being that I appreciate as much "cushioning" as possible whenever I perform a car-washing session...
I am not one that will question/doubt if
that bucket-full-amount is truly necessary, or not.
As such: Other Folks (OF) MMV.
Bob
An Aside: Have you taken delivery of your ZO6 yet?