What you consider junk is still blocks in the chain. Without people adding to the chain the value of the currency drops to zero. If the "junk" posts aren't making large amounts of money why do you even care let alone feel the need to go out of your way to flag them? New users are fleeing this place like crazy because of people abusing the down voting.
Down voting people will kill steemit. you are going to end up with a server with 10 people on it and the currency will have lost its value.
This is a new server and it is already slowing down on new members and daily I watch people quit because of the flagging. you will all be left with an empty server, a block chain that stops growing. and a currency that is worhless.
But hey, you get what you sow.
I only downvote posts where people use stolen images and claim them to be their own photography, or, where people post spam, or, when people plagiarize content.
Whether I think someone's post is "junk" or not isn't my problem. It's not fair to downvote a post just because we disagree with what they have to say. It's equally unfair to upvote content that holds little to no value.