I'd suggest that until we have a downvote functionality (i.e. a legit way to counteract upvotes), we don't bash people for using the flag.
We don't know: they might be abusing it or they might just expressing their opinion that a given post is overvalued. Which is a valid opinion that we need to respect.
Curation is not really about upvoting everything that you enjoy reading or watching. As our funds are limited, it's more about arriving at the right price for a post. Unfortunately, currently there is no tool for reducing a payout, so some people use the flag to reach this goal. I'm not saying it's OK to do it, but until the issue is solved let's show some understanding.