It's not ignorant at all, one would think that a dvd is a dvd and that's it. But it's not so simple, no, they had to make things difficult.
There are dvd regions, the US is Region 1, the UK is Region 2, and I don't know the others offhand. Basically, if you don't have a multi-region dvd player, the other Regions won't play. It's a sort of lock, and I'd imagine it was to keep people from importing cheaper dvds. I've found that computer dvd players are usually region protected as well.
