I don't think nature intended a meat-grinder.

(Personally, I rather like bacon and/or a good cheese, although fast food "American cheese" is a pass for me - gets some looks at McD's when I'll order a McDouble, hold the cheese.)

That said, having recently left a visit to Australia, I've got to say that beetroot on a burger is only slightly less gross than my local perversion in California (that being avocado.)