Using stock pics for coins is not legal on ebay. It would be worth buying, then filing a claim and leaving a negative for stock pics.
You should not be able to list dutch style auctions in the Coins section of eBay. That is just too misleading.
I couldn't care who does it. Putting a stock image of a non-modern coin and selling 10+ is misleading, especially if that stock image shows a high grade example. Now if it was a modern bullion product or some MS-69 or MS-70 crap, that is different. But certainly not all '81-S Morgan's are the same. My biggest pet peeve is seeing a nice looking coin in a listing, clicking on it and seeing the more than 10 available with 4 sold. It's deceptive. Now if you have say 4 of the same coins, then show an image for all 4 coins and let the buyer select which coin they want to buy, that would be fine. I've seen some listings done that way.
Churners gonna churn... why would they put more effort/detail into something if they are selling with stock photos? I don't blame the sellers...