The text version of the first picture is I bought Maldo's Sword Cane and Chelley's Staff of Dark Mending for 11,000g apiece and then turned and listed them for 28k and 29k. Sadly, they did not sell instantly like the tanking shoulders, but I relisted them tonight for a more reasonable 21k and 22k - I have every confidence of moving them before next Tuesday, but even if I do not, 11k for a 359 weapon is certainly something I would be willing to pay to buy from a vendor, if there were such a thing.
The second picture is of a guy whispering me about my 21k Darkmoon Card: Tsunami. Turns out he bought a Tsunami deck for 16.5k, but didn't realize that he had to wait until the Darkmoon Faire was in town to get the trinket. His deal? He would trade me his deck + 2 Maelstrom Crystals + 1000g for my completed trinket. All because he did not feel like waiting two weeks. Hey, I don't blame him, I hate waiting too. So I sealed the deal, put the deck in the bank, and pulled out Darkmoon Card: Tsunami #2 and listed that one for the same 21k. Got to keep the shelves stocked to keep the customers happy, you know?
Uber trade deals like these could be flukes, sure. It certainly is not some sort of residual business or source of daily income. But the thing about lightning not striking twice is that few people think to set up a lightning rod... which simply means more potential lightning for you.