My friend came up with this one, are there any alternatives?
"Someone who tolerates all kinds of eating habits"
(for example, both vegetarians and non-vegetarians)
Example of sentence: "Tim believes in [term-for-the-above]"
Sorry, if I wasn't clear, but my question was not someone who eats variety of food of both plant and animal origin, It was someone who doesn't mind if people around him eat food of various origins. (I'm sure you've met vegetarians who cannot bear to sit on the same table as someone who eats chicken...)