Are those really deals, though?
I mean, when I think of a deals thread, I think... "hey guys, this is a product I got for an amazing price and I wanted to let you know about it so you could take advantage of it too". Like that awesome dude who clued in me to that bargain-priced vacuum cleaner during Black Friday.
I don't think of "hey, look at this amazing 'deal' that only I got and you can't get because I scammed this ill-trained outsourced minimum wage Amazon rep to give me an additional 30% discount on top of this existing deal that they were already taking a loss on - I bet you wish you were me but you're not so ha ha".
There are deals that everyone can partake in that retailers are consciously advertising and then there is exploiting a broken system that will only do the retailer harm and is purely being done to brag and not help anyone.
You're right in that using the term 'deal' isn't the best word in this instance. And yes, when you come off as bragging about the mistake that went your way, it doesn't help anyone. However, I still think that based on what was said by others in the thread, that most of those who benefited from pricing errors were as a result of an accident and that they didn't purposely go out of their way to try and deceive the CSR.
Using myself as an example during the winter sale, the discount wasn't applying correctly for whatever reason (and yes, both items were listed as part of the sale) and I contacted a CSR who told me to go ahead with the checkout who then said they would manually add the discount. This was only after they checked each item to confirm that they were indeed part of the sale. They then proceeded to make a giant error on their part, and i only saw the discount after I closed the chat.
And to be fair, when this whole thing started, others were initially posting screenshots of the prices they got so that the rest of us could use them to see if a CSR would match it (I used a screenshot last year that someone here posted during that winter sale; i even linked this thread to the CSR).
Now, you are right, that some people shouldn't be posting screenshots of the price adjustments they managed to get just to say "look at what I got guys!" since I find that its in poor taste.
I think that in the future that if people were to get a larger than normal pricing adjustment due to a mistake on the part of a CSR, don't post screenshots about it or really talk about it. But if you do want to just so that others can try to price match it, at least be humble about it.