Honestly, I would not say that raw votes actually add much to the thread. A vote without justification doesn't actually help anyone - it's a thoughtless "Me too".
I'd completely disagree. Your perspective is skewed.
"Honestly, a dollar doesn't add much to anything," says the millionaire.
When you have a low volume of votes at all, a vote is valuable because it means that people are reading and responding, and that you can get towards having enough votes to actually writing an update. Not a problem you've ever really faced, at least as long as any of your Quests have lasted.
Which is, well, not long at all.
Edit: Plus, there's the fact that people are often busy. Actually engaging in a Quest in the sense of 'reading, voting, and, I dunno, having long conversations about it' is often beyond people, while 'I'll read, I'll think about my vote and then vote' is something far more people actually have the time for. Life's busy, and I don't blame people at all and think doing so is, again, a skewed perspective.