While legal - the following stinks of fooling the customers
In the votes they put one "attractive" choice (dazzle people with a METACRITIC score or a high discount percentage) that actually gives almost NO DISCOUNT. Sometimes they are cool games, but games that you can already get on steam itself for roughly the same price, so they are just bait to draw your vote from the larger discounts.
Here are just the last couple of choices and how people were suckered to waste their vote on next to no discount:
1) The already 75% discounted "Sacrifice" was offered to be voted for 80%. And people threw their vote on 5% of reduction!
2) "Super Hexagon" was already discounted at 80%, so they offered it at 90% and people wasted their vote on 10% diff or only 0.29$ reduction in price!!
These are just the latest two, but there have been several additional incidents that I have seen, and I certainly don't see every vote - so this is no accident.
Basically steam uses the fact that people do not really check what they gain from the deal, and makes them waste a vote, in the process they fake a time-limited deal, without having to really tank any real dollar-discount for the votes.
So - PLEASE assess the real dollar gain of your vote, and when people post somewhere: "Hey, this rocking game X is offered for a discount steam choice", please alert them to the fact that they are voting for a few dimes worth of discount on game X, while voting for game Y would have gained them several bucks. Just annoyed of this steam dirty play.