I see the electorate badge is given to people who cast 600+ votes and 25% have to be on questions. Do you think people are abusing the system and voting on questions just because they want to get this badge?
The goal of the badge is to encourage people to vote on questions more.
Sure, there are people that'll go out of their way to gain badges, but that means the goal of the badge has been reached.
Since you can only vote for any question once, and you per-day votes are capped, any 'damage' done is limited. Moreover, it's both voting up and down that counts for the badge, so it's not as if we are encouraging people to vote up everything they see.
Are you seeing a lot of votes for questions that do not deserve to be voted on?