You aren't allowed to leave regardless of how much nonsense you think the game is. If you want to leave you have to ask the other players. The majority have to agree and you have to save the replay to prove that they did.
However, this was no a "I leave because I don't want to get owned" game, it was an "I leave because I don't want to spend another 40 minutes owning" game, so I believe those 25 days aren't entirely called for.
Penalty reduced to 7 days from now.