Let's be honest, who likes all the campaign ads that happen around election time? Wouldn't it be better to divide counties into like-minded people who support the same things? That way, the representative could represent the actual views of the people in the district rather than what a slim majority believes.
Gerrymandering is a tool to preserve the status quo by those in charge. As such, it prevents the people of a community from voicing their beliefs by having opinions which disagree with the established government marginalized. When legislators have no fear of retribution due to low public approval, they have free reign to do whatever they want without risk. This undermines the idea of democracy, and gives politicians the ability to make wild gambles with our nation, knowing they have no personal stake because their reelection is all but assured. With this system in place, it is difficult if not impossible to effect change in Congress, despite it being almost unanimously despised for its inefficiency and lack of commitment.