They're hopping mad about Easter.

For those of you who are unfamiliar, "Guy Hops" is a parody of Guy Fawkes, well known in England for his role in The Gunpowder Plot to blow up Parliament in 1605.  Things clearly didn't work out so well for him and to this day, he is burned in effigy on Bonfire Night.  The poem is a rabbit-themed version of a rather brutal little ditty they made up for the Bonfire Night festivities.

As for the signage, what became associated with the Easter celebration existed long before Christianity.  If you find yourself getting offended, you're taking this post entirely too seriously.