Nothing in this world is free. Every time we use a "free" service, we have to remember we are selling something. Most often, it is our personal information. I long ago stop using any Facebook games or other apps, but I am aware that only limits how much is mined, it doesn't stop it.
We are data mined on sites like this by the ad services. It isn't a matter how selling private information, but a matter of how much and to whom.
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Mom to an amazing young adult AS son, plus an also amazing non-AS daughter. Most likely part of the "Broader Autism Phenotype" (some traits).