I think the main point of the newspaper pots is to not use plastic pots. The 'being able to plant the pot in the ground' aspect is kind of a bonus. It potentially allows a person to have less transplant shock. It might slow the interaction of the two soil systems, as it forms a barrier (which can partially remain in the soil), so removing it, has been recommended by some.
I thought the whole point of newspaper was that it'd break down in time for the roots to grow through when planted in the ground.