Ebay is full of CRAP - No Doubt, but your examples all seem like obvious pieces of crap to me.
They do qualify as knock-offs for the most part, but I am not sure if those examples would be scams as none are technically listed incorrectly or stating to be something they are not.
It would be a scam if something like the Meyerco was actually listed as "A Chris Reeve - Green Beret". That would be a scam - and B.S.
But, that is an actual Meyerco knife and Meyerco is a ligit knife company. Blackie Collins is a knife designer. But, Meyerco and Blackie Collins typically make and sell lower end junk.
A scam would be picture of Jesus burned into a piece of toast for $10,000. <img src="/ubbthreads/images/graemlins/wink.gif" alt="" />
But, for those willing to pay, value is clearly a debateable topic.... <img src="/ubbthreads/images/graemlins/wink.gif" alt="" />
Most people would feel our $100 - $200 + knives are INSANE prices for knives.
To each their own....
But, bottom line is still that you need to know what you are doing. This includes knowing "Exactly" what you are bidding on.
If you are unsure, ask questions and expect good answers prior to bidding.
If someone falsifies info in a listing or a response to questions, THEN, you have recourse of action with Ebay.
But, be warned, Ebay's general policy is to provide a tool to do business, but you are on your own after that. They will ban people, but Ebay is known to be tough to deal with. You just generally can't get anyone to help you very easily.
Ebay makes millions! But, no doubt they profit MUCH by not having much customer support.
Again, generally, you are on your own. So, make "INFORMED" decisions when buying.
Read listings carefully,
Know what you are buying,
If unsure ask questions,
Consider feedback ratings!
Etc.
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