The cats:
Mini and Tabasco like eating loads of cat grass, but save the green vomit until they are on carpet.
Pickles does the same with strange, tan-coloured stuff that must come from a special compartment in his tummy because I never feed him strange, tan-coloured stuff.

The dogs:
Buffy raids the kitty litter tray for the doggy delicatessen treats.
She taught Schnaggles to do the same.
I have seen them eat each other's vomit.
They find bones from the dinosaur era, covered in all sorts of vile stuff, and eat them.
They sniff other doggies' bottoms. For a long time.
They sniff things that come out of other doggies' bottoms. For a long time.

Dogs win!