I'm trying to find the words for this and all I've got so far is

Oh we don't eat pigs
and you don't eat pigs
it's been that way, forever
so,
'coz we don't eat pigs
and you don't eat pigs
why don't we just
both not eat pigs together

I'm confident the Mudcat collective brainpower will surely be able to help me out here.

Cheers, Rowan