The logic is simple. An editor is not going to check every single one of 30,000 SMC products on every one of umpteen thousand SMC affiliate sites.
They will check enough to see that a site is an SMC affiliate.
If two of three checked products are SMC-sourced, what is the reasonable presumption?
A) The other product is the company's own genuine unique product, whose uniqueness they desire to conceal by camouflaging it among blatantly non-unique affiliate products
B) The site is pure affiliate spam, and they have obtained affiliate status from another, as yet undetermined, affiliate program.
The simple fact is, if YOU go to the trouble of looking at 10,000 shopping sites, AT LEAST 9,990 of them will be case (B), and at least, um, zero of them will be case (A). Feel free to check this for yourself...I certainly have.
Now, as to the logic. Which makes more sense: to spend a lot of time looking at a site that in your experience is almost certainly pure spam, or to go looking somewhere else for good sites to add to the directory? The answer is as close to a no-brainer as you could hope for.
But you don't have to understand the editing logic. All you need to understand is the editing process. And, assuming you're one of the few, the proud, the ... differently sane, who WANT to hide their unique products among MLM products, then you can protect yourself against prejudice by the simple expedient of ... labelling all your products with its source.
Hiding information may get an eligible site rejected. Giving information would get the same site listed.