There are a lot of things that are legal but immoral and there are a lot of things that are illegal and moral. There are also people who game the system.
The system was set up to get viewers, not choose the best dancer. I understand that. What I condemn is the character of people who believe that being unfair is acceptable for them but not for others. Of course it's all justified by imagining, without proof, that the system is rigged in favor of the "lib." You know, libs like Donnie Osmond who won a couple seasons ago.
This is no different than a teacher passing a student because he came from a poor family. The system lets her do it so that makes it ok. And when a college accepts one kid and rejects another based on race, that's ok because the rules allow it.
Multiple votes are allowed. If they are allowed, how can it be immoral?
Do you realize how ridiculous you sound? This is not an election for public office! So it's immoral for me to vote for who I want to see move on in the contest? That is what this is - a combination or technical merit and popularity. Read the rules, dude and quit trying to moralize people for voting for their favorite! Good Lord.