Why has no other dice site that allows investing been getting close to the investments and action that JD had?
Thats because, other sites are not trusted. Recently, another dice site dicebitco did get over 7K BTC invested, but later it turned out that they were skipping nonces,
and then just a few days later, they ran away with around 1500 BTC. Also another dice.ninja ran away with the funds.
yes and now even its hard to trust any trusted site