Ugh, or large scale dairy-farm. Milk production is gross! But, manually getting milk from one happy cow is... much less gross...almost fun even.
I don't think it turned many people off milk and cheese. Actually the grossest field trip we ever went on was to a potato chip factory, the stink of rotten potatoes was overwhelming. They never took us to a pig or chicken farm though, I've been to a few at other times and those would have beat the chip factory easily. A lot of people who grow up around cows say they appreciate the small (I do, to an extent) but I've never heard anybody say that about pigs or chickens.