The thought process is that pigs eat filthy things. (philmaffetone.com)
A few days before the wedding, there is the «Blackening of the Bride,» where the bride (and sometimes the groom) are «captured» by friends and family, covered in filthy things like beer, treacle, spoiled fish, feathers, and flour, then paraded through the streets for all to see. (elitesingles.com)
Oh you can post nasty filthy things on me and that won't touch me, but when you Atheists are posting filthy comments on these boards in time when people needs supports that really matters. (religion.blogs.cnn.com)