Toons aren't known for getting along with one another. We can name a ton of Toon vs. Toon rivalries off the top of our head: Wile E. Coyote vs. Roadrunner. Sylvester vs. Tweety. Katy Perry vs. Taylor Swift.
Toons get along with humans about as well as they cooperate with each other. As we see when Eddie visits Toontown, the Toons have no problem attempting to drop anvils on humans, drop them off buildings, or hit them with trains. To them, it's funny. But to a human, it's deadly.
The thing is, the humans always end up being safe in the end. It's scary, and not funny to them…but the humans, like the Toons, don't actually die. Despite the carelessness of Toons, there are no human fatalities as a result of Toon hijinks.
The death of Eddie's brother is seen as an extreme exception, and we eventually learn that his death was a malicious act committed by Judge Doom. It isn't indicative of the actions of all Toons.
But that doesn't matter. Judge Doom uses Eddie's brother's death as propaganda to turn humans against Toons. Humans already don't like them, finding them obnoxious and annoying. Add deadly to the mix, and humans have no problem seeing Toons wiped out. If this were a darker film, we'd see human vs. Toon race riots.
We talk more about the implications of tension between humans and Toons in our theme on race. And no, we're not putting Toon vs. human conflict on the same level as racial tensions in America or elsewhere.
But it's a simplified way of looking at tensions between two communities that are isolated, yet often have to work together. Again, if this were a different movie, Roger might plead: "Can we all get along?"