I have seen this type of thing brought up in many iterations across various internet communities and the general consensus is that this kind of thing is probably money laundering. See also auctions for common electronics like iPhones selling for 10x what the going value is for that make/model.
I'm just not sure how enforceable anything is, y'know? Even if you sell over the reportable limit for sales or value, the IRS doesn't get an itemized report do they? Honestly it seems like a pretty wide-open loophole. As long as you're expensing things and "documenting" "purchases" made for resale what do they care. Not condoning it at all, I just find it curious.
My son said he was going to explain it to me today, and I didn't get a chance to speak with him. He does these credit card things. Not scams, but he buys gift cards with his credit card for airline miles. Right now he has an offer that he can earn a HUGE amount of points buying $4500 of merchandise on Amazon. I was trying to find something for him to buy, when I thought of the gift cards. That is when I found those auctions. I'll let you know when I do speak with him.