Facebook should offer an ad-free membership level for a monthly or yearly fee, or give people the option to ignore/hide "Likes" from showing up in their newsfeed.
I think they've figured out that you as a user is worth X amount more to advertisers than you're probably willing to pay a year. Would most people be willing to pay $100 a year if that is what you are worth to Facebook's advertisers?
People who have $100/year to drop on facebook are also people with enough disposable income to be worth advertising to.