Because i've heard if LN can steal the reward of the miners and it looks like terrible.
LN does not "steal" anything. Even with LN you must do some real transactions (at least two, to open and to close a payment channel). These transactions will have fees like now. It is only a way to "bundle" transactions.
And LN in my opinion does not fit all user cases. It's a better alternative for centralized online payment systems like Coinbase's wallet-to-wallet payments. With the same logic applied, these services also "steal" transaction fees from the miners.