Well, often a reason for not wanting them to track it is because you don't want them (or the US government) to build a profile on you, which could be abused e.g. by hyper-targeting content to you and thereby influencing your world view. Using something like DDG is one of many measures you can take to step out of your filter bubble.

But yes, you can turn that off in your Google preferences as well.

Sure, or DDG. But GGP was complaining about using a different product - I was merely making the point that you cannot avoid that if you want to avoid tracking.