But Facebook should not care if they get their money via ads or directly. They should actually favor fees because of less overhead. Ad prices and therefore the fee could go up until it reaches the real value of those ads making it a free choice for everyone if they want to pay a fee and keep their privacy or if they see value in ads and want to pay indirectly via higher product prices and additionally lose their privacy.

Personally I see absolute no value for consumers in ads. I like good critical reviews, not marketing bullshit. If I had the power, I would probably even consider prohibiting advertising altogether.