If Facebook were free and its company had a completely hands-off approach with your data, much like a company that makes paper notepads never looks at what you write, I'd agree.

But Facebook is a company that actively snoops and uses the data of its resources, the end-user. It's like a security guard who's paid to prevent shoplifting actively ignoring violent crimes because it's not related to stealing, or a baby food company ignoring that some metal got into their food because the food is still OK if you pick out the metal bits.