My wife goes regularly to goodwill and those prices are for premium brands and most of the time they still have tags attached or at least look like they’ve never been worn. In her experience they keep that price for a few weeks and if it isn’t sold they discount them deeply
I guess that’s true. When you go through the website they have many warnings when you select basic economy about the carry on not being included, I have to basically budget +$60 each time I’m looking for flights because they always show the basic economy first