During my first few days, I was definitely guilty of leaving some pretty half-ass comments as means of just using the site. Now that I have found a handful of users I like to check in on, I have noticed the same thing you cover here.

Many more powerful users do seek out the thoughtful comments to up vote as OPs. However, it doesn't stop whales from swooping in and upvoting other comments, nor does it stop users from upvoting their own.

It sucks.

Hopefully someday there will be a solution for this. Thanks, @bozz