Try not to think of us as individuals. The group decided that your selfie is worth around $20.
Some think it's worth more, some less.
Somebody who downvoted your $20 or $50 post, might have upvoted it at $5.
This is a consensus process.
I think the selfie's lovely, and have no problem with shortform content, but if it was up to $300, I'd be downvoting it too.