Because they don't know they're giving out their data voluntarily, or don't understand the repercussions.
In some idealized notion or legal fiction everyone might at all times be perfectly aware what they're signing up to, the reality is much messier.
Virtually no one reads the fine print, because it's obfuscated. If you have bad eyesight and are not computer literate (a good portion of the population) you will most likely not even be able to read the TOS on the average webpage. Most people have no idea what "cookies" are, or what "GDPR" means. Even if they did, there's a huge opportunity cost to doing so. [1]
Then there's network effects.
When enough people do something, it becomes a norm. I have been required by many state institutions to go through private networks whenever I need to administer something online. Yes, ones that use tracking, because they have some private/public agreement. Likewise, if everyone around a person uses Facebook, and they use it to organize their social life, then they will expect that person to do the same -- it's collectively cheaper for them than it's expensive for the individual.
I've been surprised by the amount of times I've gotten texts "oh you aren't coming"? To some event I never even heard about, because apparently everything goes through Facebook nowadays. "My cell? Just search me on Facebook."
Don't confuse tracking cookies with people opening social profiles on Facebook, Instagram, Youtube, Twitter posting their lives on the internet publicly in written, audio and visual formats. It is false to say that people don't know they're giving out their data when they're consciously doing so.
> It is false to say that people don't know they're giving out their data when they're consciously doing so.
That's missing the point, it's about the data they're unconsciously giving out. For example, my parents did not know that their Android phone could silently track their location. And even the stuff they do consciously put out often comes with strings attached.
They don't fully understand what they are doing because it's all a bit abstract and has no analogy in daily life. Well, maybe some guy (let's call him Zark Muckerberg) following you around watching you is a good metaphor.
I have a solution for this. I don't visit such websites. They want to harvest my data, I won't give them my data. Either comply with GDPR or lose a visitor. Simples.
That's because they're neither a writer not is it an article. Take Forbes with a grain of salt, their authors are mostly half-literate unemployed students writing "blitz articles" for about 50p/100 words.
"The administration of President Donald Trump just made it easier for for-profit colleges to get away with making fake promises about things like graduation rates and job placements."
This is where I stopped reading. Pretty much the first sentence. False advertising has been a problem for at least two decades now, mostly in Law and nothing has been done about it. People started talking about it only recently after the rich kids got affected by the false advertising; their parents spend $200k-$300k on a Law degree with a Bar test only to find out that their kids can't get a job that pays more than $50k because there's been an abundance of lawyers for about twenty years now.
Same goes for IT and all sorts of BS degrees ala marketing, communications, david beckham studies etc... besides you don't need somebody to tell you:
"Hey, save your money you don't yet have, that degree is useless! You can do that without having one."
You only need half a brain cell to figure this for yourself. It's not brain surgery and if you do need someone to tell you that, then you really do need a hard lesson.
True, this is a huge aspect that is not discussed enough. Even if we reduce carbon intensity of our energy per capita, we may keep emissions too high simply by providing energy to many more people. I believe a huge aspect of reducing future emission would be educating women and families in developing nations, helping them through the epidemiologic transition to lower birth rates/family size much quicker.
