Voting is immoral too.

If I don't support the potential outcome, how could I justify participating?

Here's a scenario for you:

11 people in a room. They decide to take a majority vote to murder one of the 11 at random. What's your vote? No? What happens in the case you're outvoted? You are now complicit in murder. Vote yes? You are now complicit in murder. Casting your vote is your acknowledgement that the you accept the results. The only moral action is to object, conscientiously and refuse to participate.

Now stand in a room of 300,000,000 people where the end result of your participation is endless evil and murder. Congratulations.

> If the majority of people in your country agrees that wealth redistribution is bad, then just elect a government that will stop doing it.

That is why they (the upper class) came up with progressive taxes - so middle class (the minority) would subsidize lower classes (the majority). Basically you suggest a pack of wolves and a ship to democratically decide who will be eaten for dinner.