I think what you guys are getting to here is that it is wrong to intentionally mislead. Especially when cash is on the line.
To to pull magnets and rebuild "full boxes" that you know are devoid of magnets is as messed up as re-sealing unopened packs.
The example of Mark "cherrypicking" boxes with gold flashbacks is not the same thing. He didn't intentionally mislead, or even set out to do any cherrypicking at all. He just figured out some odds along the way. It's key to note that, in retrospect, he realized he could have provided more complete information, and thereby have made his transactions more fair.
It's closer to a situation wher you think a certain sticker isn't worth a lot, telling that to someone, then buying the sticker from the person, only to find out months later, that it IS worth a lot. Maybe not exactly, but similar.
With regards to t-shirt guy and to Jay's use of Greg's scans. I don't believe Jay OR the t-shirt guy set out to intentionally mislead anyone (which doesn't make their actions "okay" but it's an interesting clarification). I'm not going to go back and re-read everything so I COULD BE WRONG, but did Jay ever deny he was using Greg's scans? Did he ever try to claim that Greg's scans were his? I think he just maintained (and may still) that it was "okay to use them" in the way he did (because he touched them up, color-corrected, etc) - at least until it was brought to his attention that, legality or not, it wasn't ethical. At least to a great number of us (me included).
Similarly, the bootleg t-shirt guy was straight up about what he was doing, he just didn't seem to be bothered that it was in violation of copyright, and an existing licensing deal for Wacky Packages t-shirts. The t-shirt guy should stop selling bootleg shirts. If he wants to make them for friends, that's probably still in violation, but no one will ever know, or try to stop him. Sounds like he might not be stopping, which IS pretty messed up.
Jay should have taken down Greg's scans, and I believe he did so pretty quickly. I'm honestly not sure if he ever tried to mislead anyone, but I don't think so.