I'm not sure if that is the case, but if it were that's not really my problem :)
This is the place I generally use, but simply because it is most convenient for where I live (it's about 3 blocks south of I-290 at the Cicero Ave exit)
I don’t think this is really true. Kitchen supply is an example with stores that are open to regular people and there are still deals compared to consumer cookware.
If you go to a restaurant equipment liquidator you can find some good heavy-duty pots and pans, they likely won't be "attractive" as restaurant kitchens don't care about that. Be aware that most of the cooking equipment and appliances won't be usable in your home kitchen because your electrical circuits won't be adequate.
You can pick up beverage glasses and cups, plates, silverware.
There is of course quite a range between totally illiquid and totally liquid.
My best finds for second hand goods were found by intentionally searching obscure marketplaces. Telling a few ppl on HN probably wouldn’t make much of a difference, making a viral TikTok video about it might.