They’re not stealing it, you’re giving it to them in exchange for using the products for free.

This is not true, as can be seen from Facebook maintaining 'shadow profiles' on people who don't have actual Facebook accounts but can in any way be connected to them (eg through third party data).

Also, Facebook encourages users to tag people in photos even if they don't have a Facebook account.

It seems dishonest to frame it as a market transaction when it clearly isn't. There is no explicit agreement, and most users probably don't have the slightest clue what data they're giving up.

Google ads trace you, and Facebook tracking pixels keep profiles on you even if you never used any services. It’s literal theft. It’s just allowed for corporation but if I do it, it’s harrasment and stalking.