It's a method of circumventing the matchmaking system (often as a way to play with friends who aren't near the same rank), one not unfamiliar to League of Legends players and other free-to-play games.

When I'm up against such a player, there's no tool within the reporting system for me to flag their account—and why should there be? As far as Valve's concerned, that player is another legitimate customer. Solutions like IP banning would be over-aggressive: what if that account is legitimately a csgo skins sale friend or sibling?

I want to see the CS: GO community grow, but I bemoan that the game I play most going on sale will probably mean that I'll encounter a few more cheaters and rank-dodging players in the next month or two. To give Valve credit, this isn't the cheapest we've seen CS: GO. In December, January, and March (the latter coinciding with the EMS One Katowice tournament in Poland), the game was slashed by 75% to just $3. 74. The 50% cut over the next two days may be a small compromise, but I don't doubt that it'll invite more players to circumvent matchmaking and play illegitimately.