"Why can't people just say they were moved? Why do they have to say it's sappy?"

This quote by Casey Affleck is a commentary on the way individuals frequently express their feelings. He is recommending that individuals must be more open and truthful about their feelings, instead of using terms like "sappy" to describe them. He is indicating that individuals must be more comfortable expressing their feelings, which they need to not be ashamed of being moved by something. He is likewise recommending that people ought to be more accepting of others' emotions, and not evaluate them for being "sappy". This quote encourages individuals to be more open and truthful about their sensations, and to accept the feelings of others without judgement. It is a tip that feelings are a natural part of life, and should be accepted rather than concealed away.