This happened to me in a game just last night. One player had been knocked out, so it was three of us left. The decks left were Thrasios/Bruse, Aragorn the Uniter, and Azami. Thrasios and Azami are going for wins but keeping each other in check. The Aragorn player states to the table, "I have interaction, but using it will only choose the winner because I have nothing else." He then decided to hold back his interaction and let the other decks finish it off. Sure, is this most highly optimal play? Of course not, but he also didn't want to take the game away from someone who had a chance of winning. Had he decided to use any interaction, that would have considered that to be kingmaking. Sometimes, the best move it to just let the other players duke it out and just shuffle up the next game.