You can never know what might prejudice someone else against you. Maybe you get flagged as being gay when you aren't, or as holding certain religious or political views that you don't. Extremists, activists, and protestors can go to a data broker and buy up lists of people to harass or attack. Data brokers have already been caught collecting data on people who visited Planned Parenthood locations and selling that data to anti-abortion groups.
You could be incorrectly flagged as having more money than you do, causing companies to charge you more than they charge your neighbors for the exact same items. Discriminatory pricing has been happening for a very long time. Just using a different browser can cause prices for some online services to change. (https://www.bostonglobe.com/business/2014/10/22/online-shopp...) For example, Apple users might be seen as having/spending more money and so the prices they get for hotels and airfare can be higher. Increasingly, brick and mortar stores have been trying to get in on the action too. (https://link.springer.com/article/10.1057/s41272-019-00224-3)
If you have a browser extension that randomly visits sites and clicks on ads. Maybe it clicks a bunch of ads for alcohol or marijuana. Maybe it clicks on ads for mental health services, addiction/recovery services, or suicide hotlines. That data can be used against you in court during a divorce/child custody case. It might make a company less likely to hire you. It might cause your health insurance company to charge you more.
Maybe it clicks on ads for DUI attorneys and suddenly your auto insurance rates go up. The company isn't going to tell that's why. They might not even know why. their algorithm just decided you were more high risk than before.
Any data for sale, accurate or not, is going to be used against you. The people paying data brokers for information about you aren't doing it because they want to help you. They want to help themselves at your expense. And its insane how many people are buying up that data and using it whenever they feel it might give them even the smallest advantage. Companies are using that data to decide things like how long to leave you on hold when you call them. (https://www.nytimes.com/2019/11/04/business/secret-consumer-...)
You could be incorrectly flagged as having more money than you do, causing companies to charge you more than they charge your neighbors for the exact same items. Discriminatory pricing has been happening for a very long time. Just using a different browser can cause prices for some online services to change. (https://www.bostonglobe.com/business/2014/10/22/online-shopp...) For example, Apple users might be seen as having/spending more money and so the prices they get for hotels and airfare can be higher. Increasingly, brick and mortar stores have been trying to get in on the action too. (https://link.springer.com/article/10.1057/s41272-019-00224-3)
If you have a browser extension that randomly visits sites and clicks on ads. Maybe it clicks a bunch of ads for alcohol or marijuana. Maybe it clicks on ads for mental health services, addiction/recovery services, or suicide hotlines. That data can be used against you in court during a divorce/child custody case. It might make a company less likely to hire you. It might cause your health insurance company to charge you more.
Maybe it clicks on ads for DUI attorneys and suddenly your auto insurance rates go up. The company isn't going to tell that's why. They might not even know why. their algorithm just decided you were more high risk than before.
Every data broker is creating a dossier with your name on it, and they are stuffing it with every scrap of data they can get their hands on. That data can cost you a job or a rental contract (see https://nypost.com/2022/12/20/how-employers-spy-on-your-sear... and https://themarkup.org/locked-out/2020/05/28/access-denied-fa...).
The data being collected on you can get you arrested or questioned by police. (see for example https://www.nbcnews.com/news/us-news/police-google-reverse-k... and worse https://www.nbcnews.com/news/us-news/google-tracked-his-bike...)
Any data for sale, accurate or not, is going to be used against you. The people paying data brokers for information about you aren't doing it because they want to help you. They want to help themselves at your expense. And its insane how many people are buying up that data and using it whenever they feel it might give them even the smallest advantage. Companies are using that data to decide things like how long to leave you on hold when you call them. (https://www.nytimes.com/2019/11/04/business/secret-consumer-...)