I had reels of strings from Prince, Wilson, Gosen, Luxilon, Kirshbaum, Signum Pro, Pros Pro where I tracked string used by reel. When I got to the point of tracking saying that I did not have enough string for another complete string job, I measured the remaining string. Every one of those reels had more than what was stated on the reel label, e.g. 665-670’. This is a personal observation based on reels under my control either my purchase or clients’ purchase.
I get the left overs for weed eater and for crosses.
edit: Liking string has no basis for accepting the fact that the package is short. Send the packs back and buy a reel. Track string usage and if it also comes out short, complain to the seller and to the company selling it. In the US, it is illegal to shortchange volume, length etc. So? Are you sending the packs back or eating the shortage yourself?