> However, "liking" their pages is out of question. I will not support them, I will not help them further their propaganda, their hateful rhetoric. I would like to understand them, but in no way do I want to support them.

Consider the possibility that if you and your friends "liked" pages of "extremist" groups that you disagree with, then when they pay to boost a post, part of that money will be wasted on showing it to you. So while you are supporting them (by making it seem like more people like their page), you are also weighing on them financially. Not a huge impact in either case, but worth considering both sides of the coin.

I agree that there should be a way to follow-without-liking. That would make it possible for advertisers to use clickfarms to impair their competitors, by flooding them with fake followers who then suck up the competitors' advertising dollars. There's always an unintended consequence!