I have ordered five pairs of pants from Lands End last year and two pairs so far this year and all items came in plastic bags and with little to no tags. LL Bean is the same; items are delivered in plastic bags with few if any tags. I don't understand the problem with delivery in plastic bags and no tags as it is more environmentally friendly. If one is giving a gift, I would think that the company would provide something (gift card, tag, etc.) so that the receiver would not think that one shoplifted the item or bought it used at a flea market. I don't know what the Gap and JCrew are doing, but Brooks Brothers and JosABanks sent their online orders to me in boxes with plenty of tags.
As for returns, I always thought they went back into stock if they were in new condition. About twenty years ago, LL Bean opened an outlet store in an outlet mall (where else?) just off I-95 in Maryland, between Baltimore and Philly. That store sold everything that didn't sell at all of their retail stores and their outlet stores nationwide, plus items that had been returned and couldn't be sold again (new shirts monogrammed with someone's initials). About ten years ago, that store closed along with that outlet mall. I have no idea where they get rid of such merchandise today.