Personally, I'm thankful that Dappervolk decided to split the monthly set between Oran and Pai. By having one part of the set locked behind potatoes, it creates value for potatoes and acts as an important "gold/potato sink" and essentially gives free to play users an opportunity to trade for Pai's half.
I have no complaints about Oran's half not being included in the Mothlike Silver Chest. I do, however, agree that an $18 price point is quite expensive even if it did include Oran's half (which I am personally against). I know the higher price point is to incentivize the Gacha aspect, but it'll still cost a minimum of $10.80 for Pai's half.
I personally do not and won't spend real money on Gacha/RNG/Loot Boxes and right now the $18 price point is too high for me to ever considering purchasing.