It's amazing how many different opinions there are of NWT on ebay. I've even found it to mean, 'Yes, it's been used...a lot, but I still have the tags...just not attached.'
Yes exactly TooManyWantMore! And this is very very common with Balenciagas. The city bags have short arm straps and are worn close to the arm pit, and I would get bags that had sweaty gross arm straps that were listed as nwt.

But I digress...this is the Coach forum

I avoid buying bags right after the holidays or June because I find that many of them were bought for special occasions and parties, proms, vacations, etc and have been used and listed nwt because the tags were saved.
People complain about the markups on the outlet bags sold on ebay, but at least most of those are being listed by professional shoppers who have a business and are just trying to turn a profit. They are not using the bags. I have gotten to the point where I can usually tell if a tag has been reattached to a bag from the photo. It will be in a weird place on the bag, or it will be missing a piece of the tag, etc...
I expect a lot of photos when I buy on ebay, and sometimes, if I think the bag is being listed as nwt and is used, I will ask for more photos.