Why is it important for everyone to cast a single vote that itself won't make a difference, but unimportant for one yo choose not to partake in an industry that

Why is it important for everyone to cast a single vote that itself won't make a difference, but unimportant for one yo choose not to partake in an industry that they either disagree with or distrust? If one vite is worth casting simply fr the fact that it can help a person think more deeply about issues that matter to them, certainly the same could be said for how they choose to spend their money as well.