So was EBay saying the seller was scamming EBay, or scamming the customers because the seller wanted people to buy from his/her other source? I'm not sure what EBay was actually saying, but it sounds like EBay was the one the seller was trying to scam. The seller's other source might be a legitimate business and thought they could drum up more customers by using EBay. Not good for EBay but it wouldn't be a scam to the buyers.