They may not be taking money out of the system, the system probably creates it as needed.
However think of it this way. Whales get 20 great votes in a 24 hour period. Meaning they can vote 20 times and each user would get the max available for that particular whales vote.
This could be $200 per upvote, or even $2,000 per whale upvote.
Who are they most likely to upvote? You? or their friends who are signing up and making posts? Or even their own shell accounts?
Maybe they give 19 upvotes to friends, and 1 to the public. Who knows.
15 votes and it doesnt matter. The whales control steemit, the upvotes are most likely going to friends and content is downvoted even if it was previously getting a lot of upvotes from users as being helpful.
Just have to wait for someone to take this idea, refine it and run with it.