>>7443714A lot of times old seals fail and lift up by themselves or slide and look like they've been tampered with. 20 year old + glue and thin tape doesn't always hold up the best. So if they're looking bad, some sellers will just take it all of the way so there's no doubt and they can guarantee it's complete.
I wish Lego still made the old-school flap boxes that displayed the pieces / figure.