i think it depends on the offer,if its just a simple downsell (Get half price shipping click here) VS someone actually speaking to the person online then i would think you definitely get credit, if its someone reselling the person then you might not.
I think these are the details that if you focus on it too much then you lose sight of scaling and build conspiracy theory's, Run the offer that converts the best, and test various offers (try to test by using different advertisers, some advertisers will have multiple brands so talk to your AM)
In the end find the offer that yields the highest returns, if you pick on the small items youll lose sight of what works out there, test, test, and test some more.