It's not about game companies. The companies actually don't care that much, they have sold the game, and spent our money already. If they ever react is just because of the pressure from gamers.

Also, it is not about cheating in your single player game. No one really cares about that. Want to enable god mode and insta-kill every baddie? Go for it.

Cheaters in online competitions simply ruin the game for other players. Cheaters destroy online gaming communities.

So of course, in online gaming communities, cheating is seen as one of the worst offences someone can commit.