This site had REGISTERED USERS: 8,716,261.
It's hard to roll a number to get high reward. I think they can't survive for a long time if everyone are easy to roll high number

I'm really not sure. I know with the number of refs I have at least one of them a week would be at least a 10k sats earning and that hasn't happened for quite a while. It's not the decrease due to BTC price, I mean 1 or 2 would be way out ahead of the others.
I guess we'll have to wait for the site owner to answer.