Many cheeses in the US are vegetarian, as they use a microbial rennet source. Still, there are places that use animal-derived rennet sources. Products made with animal-derived rennet sources are not vegetarian. Rennet that comes from an animal is from the stomach lining of a slaughtered cow, sheep, or goat. Some places also use rennet derived from slaughtered pigs. So to answer the question that many people have:
Are Cheez-its vegetarian? Do they use animal or microbial sources of rennet?
When asked that question on their Facebook page, here's what their exact reply (pictured below) was:
"This is a great question! The rennet in all of our Cheez-Its comes from a microbial source, not an animal one. I hope this answers your question. Thanks for being a fan of Cheez-It! -Kyle"
Yes, because they use a microbial source of rennet Cheez-Its are vegetarian. They are not vegan, because they contain animal derived ingredients.
Today you can find great vegan alternatives that are available online and in some stores. Be sure to try the tasty Earth Balance Vegan Cheddar Flavor Squares.