Supposing there is a monopoly, that would mean they would be able to sell the DVDs at any price they want. In a bad case scenario the DVDs would cost us the same price the japanese have to pay for them. In a worst case scenario we would be paying even more. Quality may drop too since there is no one else they would be competing against. In almost anyway you see it, is always a "lose" for us.
Also, it that were to happen, I'm damn sure piracy would rise. Maybe not much since anime (as far as I know) and such is one of the most pirated things on the net, but a rise is a rise.
"I settled for that shriek. Those dull vacant eyes... oiled cabbage stench of her...! [...] You know what? I'm sorry if I'm not gonna do this the way you want me to or the way you might. But I will not make an angel out of someone who wasn't an angel...!" -Chief Tyrol, on his beloved wife.
Have you heard about the saying that goes something like "drunk people and kids tell no lies"? Well, that's just a fallacy.