On twitter you just block the accounts that are sending you promoted tweets. Eventually, you'll run out of people trying to target you. You have no recourse on Facebook.
You'll still see promoted tweets, they'll just get more and more strange as you collect all the bigger corporate brand accounts in your blocklist.
Strange random ads are ok compared to seeing creepy demographically targeted ads. Also, there are only so many national brands who are willing to spend money indiscriminately.