Straight from the horse's mouth (Valve employee):
So you're aware, giving away free stuff while asking people to vote for your game or implying that users should vote on your game will not get the game Greenlit faster. It just makes our job more difficult to tell whether customers are interested in your game or just thankful that you are giving out free stuff.
When you give away copies of your game or other items/points/coins/whatever in exchange for votes or views, you put us in a really uncomfortable position. We do not think these votes accurately reflect customer interest and it makes our job harder in deciding which games customers would actually buy and play on Steam.
Additionally, when you give away something for votes or views, then every other developer on Greenlight thinks that is now the thing they need to do in order to get noticed. We don't think that is healthy for the system or really what customers want.
We understand that running contests or giving away copies of your game can be viewed as a form of marketing. But for the purposes of Greenlight, we don't think that giving away copies of your game in exchange for votes accurately reflects genuine customer interest.
This is something we continue to take into account when evaluating titles to be greenlit. The result is that it may take significantly longer for your title to get Greenlit, as it is much more work for us to try and understand customer interest in a title that has collected some unknown number of votes in this manner.
Source:
https://www.reddit.com/r/gamedev/comments/5ndmjc/does_anyone_have_thoughts_on_the_orlygift/dcb1l04/