Everyone is talking about how if we ban gambling here, then we should ban it from the rest of the world, and that is not relevant. Since Meepcraft is PG, and the world is obviously not, your analogies and logic make no sense.
That said, I think dicing does have a negative effect on Meepcraft, just because of the bad behaviour it instills. Rage quitting, losing money, gambling, and getting scammed are on this list. All of this can lead to arguments.
However, I understand it's a nice way to earn a lot of easy money, but I feel the negative effects far outweigh the qualities.
Edit: +1