One of the benefits is that ingestion is flexible -- In general movies can be distributed via broadband (well in advance of release too, as the files are unplayable without decryption keys). For stuff like film festivals there's usually crates and crates of HDs :-)
This is why bandwidth isn't really a gating concern -- it's a mastered, offline format, so you don't need to squeeze all the possible bits out of the final package.
