No, that is simply incorrect. The other, and I think main difference is in the contributor field when an image is viewed as a purchaser would view it; as a result of a search. The contributor line for Stockimo images includes quite clearly the word "Stockimo".
At least as it stands the fact it is a Stockimo image is stated. If it wasn't, the chances of a buyer not paying much attention and buying an image that turns out to be only 1536 x 2048 pixels (for example) are greatly increased.
Back to the topic of monitoring both S images and non-S images in the same way and in the same place, I think that has merit.