Trying to put things into perspective for the 'Superman Survivors':
If the movie sticks to the general 'Superman' comic book story then most of the people on earth will know about Superman coming from a distant planet, being the "sole" survivor, and landing on earth. It's like how everyone in the comic books know Superman is from Krypton and his only weakness is Kryptonite. In 2 year's time the whole, "I'm from Krypton and I arrived here as a baby" bit might have come out already.
So Zod's attack on Metropolis and all of Earth was unprovoked. It's not like Superman purposely led him there. Superman arrived as a baby and had no knowledge of other possible survivors. Now, here's this alien who grew up on Earth fighting off an alien who swooped in on a scary spaceship and is trying to destroy your planet with dubstep. Most of Metropolis was destroyed by the dubstep machine rather than Superman & Zod's fighting. I think most of the death can be/is placed squarely on Zod's shoulder, so he will be the one where the anger is mostly directed at.
2 years after the attack it's not a stretch to see people celebrating Superman for saving the entire world at the cost of a major city which he did not cause most of the damage to. Again, I really think that whole fight scene could have been handled better with little effort but that's the way it is.
As long as not everyone is ok with Superman being on Earth will this all be alright though. Surely in 2 years there have been many detractors from the whole Superman hype as well as supporters.