I believe it's more along the lines of "I'm having a conversation with you today because I value and care about you and our friendship etc; I want to be the kind of person that shows up for others and leaves people I interact with in a better place/mood/etc."
Instead of being the person not aware of their moods and carrying resentment over the smallest slights so they end up bitching about it to everyone. If one never chooses, or "vote", for the positive/uplifting inter/action, then they are "voting" to keep being the person who always has something to complain about.
Similarly, the smoking example, choose to be someone who cares about their health or the person who could not care less. Better is defined by the user. But either way, it will certainly build, or describe, the type of person they are choosing or "voting" to be.
Though, its really just stating the obvious. The more you do or don't something the more those actions become you. The "votes" on those actions don't have to be overt. It's like they were trying to find a novel way to restate the self-help quote: "Watch your thoughts, they become your words; watch your words, they become your actions; watch your actions, they become your habits; watch your habits, they become your character; watch your character, it becomes your destiny." (-attributed to the usual suspects)