Shoe-throwing = ritual protest. Pig head-throwing = racist incident.

Thanks to Bosch Fawstin for the Robert Spencer graphic.
Throwing a pig’s head into a mosque, or into anything, is obnoxious, reprehensible, and always and everywhere to be condemned.
That being so, why the double standard?
UK police bow to “Islamic sensitivities,” allow Muslim protesters to throw shoes
Isn’t throwing shoes just as potentially “distressing,” as well [...]