because they're the ones who know 100% that Planned Parenthood isn't maliciously "harvesting baby parts" for profit, but they think the ends justify the means, so they're more than willing to fight on that lie, and feed it to the people who actually believe it. People who include psycho wingnuts like this guy who either think they're doing gods work, or some kind of vigilante justice for babies.

Of course, they'll all just go on claiming that since they're not telling folks to incite violence, that they have zero culpability in shit like this happening, but what the fuck do you expect telling a bunch of angry people (many who are unstable with guns) about the taxpayer funded baby killing factory down the street?