It's the same reason why we have to codify "thou shalt not murder" into our laws - because some people are selfish, greedy, opportunistic assholes, and you have to twist their arms to get them to behave like civilized human beings.

In an industry (and this includes ours too, techies, don't be deluded into thinking otherwise) that's driven by the bottom line, practically without morality, perhaps the best argument you can make is something like this.