I had the same problem with both gravity and Hugo. I found a Reddit post that also talked about this. It seems to be related to how you might have redeemed some digital codes when buying DVDs. If you got the movies and iTunes from redeeming DVD codes, seems that they are a different version than the ones that got upgraded to 3-D. The writer suggested gifting the movies to yourself, but that’s tough to do because they removed that from most of the iTunes store apps. I ended up buying a bundle with gravity in it, and that fixed it for me, but I’d rather not do that for all of the movies I got through buying DVDs.
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