Antonyms for "pitches in to" include "abstain," "decline," "refuse," "neglect," and "ignore." When someone "pitches in to" a task or project, they are actively participating and contributing to its completion. However, when someone chooses to abstain or decline, they would be choosing not to participate or contribute. Refusing would involve actively rejecting the opportunity to pitch in, while neglecting or ignoring the task at hand would demonstrate a lack of interest or attention. It's important to consider both the positive and negative connotations of language, especially when it comes to teamwork and collaboration.