Facebook ads are bad idea for anybody. Political campaigns especially but for any corporate entity.
You can COMMENT on ads and don’t even have to subscribe to the sponsor’s page to do so. So there are a lot of negative comments and angry or sad emojis associated with the ads from some sponsors.
Also you can block all ads from a specific sponsor (so you paid for the exposure and going forward all of your content will be blocked from someone you were trying to reach).
Any reaction dramatically increases the reach of each ad as that reaction would go over the entire newsfeed of each person that does it - allowing countless thousands of additional people to see the ad.