system
Given the following post, respond as if you're commenting on Reddit:
human
[Warcraft] The story says "Arthas bad" for you-know the infected villagers, but what were the possible never-mentioned alternatives?

So Arthas decides to kill all the infected villagers. 

They keep going on and on about how it's wrong and he became evil while trying to do good and therefore he must be stopped, but they never explain what were the supposed alternatives, nor what would be the cost...

So what could have been done instead?
gpt
There was no "good" alternative, and that was the beauty of the Lich King's trap. No matter what happened at Stratholme, Arthas was going to be pushed to the extreme edge of sanity, and forced to pursue Mal'ganis to Northrend. 

Uther and Jaina would have preferred to surround the town and observe, then likely try to engage the Scourge somewhere away from the civilians. They wanted to take a more compassionate approach, even if that compassion involved a strict quarantine of the entire city that would have looked and felt much like a siege. 

Unfortunately, all of the townsfolk had eaten the plagued grain before Arthas arrived, and they would have all become mindless undead in the fullness of time. Which would have caused them to swarm the soldiers surrounding the city, or worse, attack the Alliance forces from behind when they tried to deal with Mal'ganis in a "safe" location. They would have been doomed, and Arthas would have witnessed that destruction and suffering firsthand. He would have mindlessly pursued Mal'ganis in a quest for revenge either way.