Some people are wrong. These people in particular.
Agreed, but ultimately the government is the arbiter of what constitutes harm.
Look at the Michael Vick case. You actually have some people suggesting that since dog fighting is a part of the culture of people like Vick, who are we to judge? They are somehow suggesting that in their "culture" no harm is being done. And that government has no business in judging that.
But of course we as a society have decided that indeed harm is being done. But why? What are we basing that on? Where does the morality code that says what Michael Vick is doing is wrong come from? It's got to come from somewhere.