Because while you're worried that you'll get an ad for a clothes iron after searching for one, they're worried about how they're going to make rent this month.

I feel the biggest problem is most of this happened before there was awareness. This isn't something an individual can stop anymore, it needs an collective massive effort to stop, blocking ads or trackers is only fighting the symptoms not the cause. So we need these practices to not happen, somehow. Legalisation is the obvious answer and there lies the problem, this is one thing where technological advancements fast outpaced legislation, and it doesn't help that big tech generally goes the way of practicing questionable or even illegal methods simply waiting to be called upon, then get away with empty promises, operating internationally they've gotten too powerful for a single government to deal with. So we need intenternational governmental cooperation in an field where those same governments benefit from this data, good luck with that. (is love to have a purely technical solution like blocking ads to work, but the problem isn't a technical one)

People have busy lives and other things to worry about. Even if they knew this were happening, no one has the time or energy to do anything about it. What have you done, other than post the obvious?

Because there are no noticeable effects. You get really well-targeted ads once in a while, but that's about it. Fighting back, on the other hand, brings a few inconveniences.