Because they charge a premium for every token sold, the current cost is 7 sats and to become a level 1 premium member it would cost 17,500 sats. When the token was 50 sats and they charged 51 sats on FBC, it cost 127,500 sats. The cost was 7x higher back then but the rewards were expected to be 11x higher. As high as the price was back then, we could recoup our investment faster.
The premium program got disbalanced after FUN price crashed. They didn't keep it fair for premium members who bought FUN when it was more expensive. As FUN lost price, they should have balanced the premium tiers costs accordingly, just like they do with faucet hourly rewards and WoF rewards.
This way they would also help decreasing the supply of FUN on the market, as more FUN would be locked or idle on the wallets.
Anyway, I don't think they even cared about making it work at all...