If they farm them on all their characters every day it would be all that hard to amass that amount rather quickly. It may be their major way to making money in the game. I've never seen anyone bot mining especially since they added the annoying directional codes that pop up every attempt or two.
They once said they would bring a way for people to make Rewards Points easier (it was when Star Planet was removed)
Now all they did has been giving us less ways
I know but I feel like it balances out for rare occurrences when there is only one a week. For that once a week maintenances I go all out and use soap and shampoo.