There is some controversy on the internet if Cheetos are vegetarian or not. In fact, there is some controversy if Cheetos have pork in them or not. This 2002 post says Frito Lay said Cheetos were/are vegetarian (except for one unusal variety).
Now aside from the fact that humane (not cruel) milk has mostly disappeared from the market and been replaced with factory farm milk, I have tracked down a vegetarian option: Bearitos Baked Crunchitos. I just got an email from Hain:
“Thank you for taking the time to contact us regarding our Baked
Crunchitos. We strive to maintain the highest quality products and
appreciate your patronage.
The enzyme in this product is from a vegetable source. There are also dairy ingredients in this product.”
All of this confusion could be avoided if food sellers would label the source of enzymes used to make the cheese in their products.