What's the age of the boxes? As in, are you opening the new-and-improved stuff they released only a few months ago, vs stuff from a few years back? I can't say as I've noticed too much difference between boxes, but then I've never shot acros in 4x5.
(also, I'll presume you're shooting new-bought? I've been caught out by second-hand films missing internal boxes and bags before: I got a box of 10 Provia 100F (for only a few bucks) sold as 'some used', when i got it home I went to try and 'feel' through the bag how many sheets were left, took the top lid off and, woops, no inner boxes, nor bag. At least there was a cardboard over the sheets so I've probably only fogged the edges, but nevertheless it's been relegated to 'test shot' film...)