For nearly 40 years, I've frozen LF film in/out of Ziplock bags (sheets are in the plastic bag as provided by manufacturer) and done the same with roll film. Over the years, I've read that you shouldn't remove film from the freezer, thaw, load (in the case of sheet film), then return the box to the freezer. I've done this very thing repeatedly and never had an issue. In my case, I've never been too concerned about how I handle the film; others may have had issues and that's why they do something different.