Apart from the fact that lynching inactives is always a losing play for town, we can't lynch inactives when it's day 1.
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The reason lynching inactives is a waste is because it provides no useful information for town to analyse which is a waste of a day and essentially gives the wolves a free kill. There's also the fact that most inactives are going to be villagers because power roles are always going to be more invested in the game.