They are not thieves.
Stealing data is the most misunderstood fact about big tech companies and data privacy. First of all, they mention which data they collect and why in the privacy policy statements. However, the majority of the users will never spend a minute reading their privacy policy. But they will spend hours arguing about data privacy later. If you don’t agree with their policies, you can avoid using them. On the other hand, if you don’t like to share such information but still like to enjoy it — use a separate email or phone number, avoid sharing personal data, and enter some fake data — Nobody cares.
They do not steal your data and reveal you to outside individuals. Instead, they will feed your data to machine learning algorithms to offer you a good service and also to display personalized advertisements on linked platforms. Sometimes, I get the use of personalized advertisements. For example, I found pretty good cloud service providers thanks to Facebook advertising.