seller telling me they sell hundreds and no problems
That's typical. Yes, they might sell hundreds and the average buyer is not sophisticated enough to know where the fault lies, and it's too cheap to go to any trouble over. The eBay system is flawed because it is difficult to give feedback about a product – eBay was originally a platform for flogging off unwanted items, not retail new items. Feedback is about how trustworthy a seller is, and if a seller meets their obligations and says "sorry, I didn't know" it's hard to claim they are actually fraudulent.
There is room for benefit of doubt: these sellers buy stuff in bulk from the likes of alibaba, and the product
might have changed without their knowledge. Some sellers don't even handle the product, they only act as a go-between and the product comes to you direct from the wholesaler (I try to avoid those, but I frequently find sellers are not honest about where the item is being shipped from – I get snotty about that in my feedback if I was led to believe I would receive the item through UK post).
So maybe that listing used to deliver a 3070 dongle... all you know is
you didn't receive a 3070 dongle. I have expressed concerns about that previously, elsewhere in this forum.
I had a problem with a QI charging transmitter from China (of course) – the item received looked for all the world like a receiver, didn't look like it had the necessary components for a transmitter, and I couldn't make it work as a transmitter (or a receiver, but I might have blown it up by then), but the seller absolutely insisted it was a transmitter and would only offer me a discount not a full refund. It was that latter detail which resulted in my negative feedback.
Don't imagine trading on gullibility only happens on the Internet. I have seen cheap products in the bargain discount shops which could not possibly do what it claims on the label (eg a cable with a digital video connector on one end and an analogue video connector on the other end). If people are stupid enough to buy stuff, other people will try to make money by selling it to them (age defying face creams, anyone?).
The moral:
caveat emptor (let the buyer beware). You might think you have consumer rights protection, but they are difficult or impossible to enforce. Not even Trading Standards wants to know these days, an enquiry from an individual (ie me, about a case of a retailer denying their legal responsibility under consumer rights legislation) gets redirected to Citizens Advice (and all Citizens Advice had to say was to refer me to consumer rights legislation... there's a hole in my bucket)! We now (if we ever did) have no rights in law unless we (individually) have the financial resources to buy the attention of a judge. There are no public agencies who will act for you, so where the damages are less than the cost (in money and effort) of a Small Claims Court action,
there is no protection (and that ain't gonna work when the seller is non-UK anyway).
Dishonesty rules, honesty and decency are the underdogs.
