The same laws exist for any industry. You can't walk into a supermarket and start recording them while unleashing a barrage of questions. There's many reasons for this including:

Some techniques are proprietary. Farmers make their living off their farms. Most business owners don't want someone coming in and recording the different ways they conduct each aspect of their business.

It's disruptive. At this point farmers are essentially dealing with paparazzi, similar to a celebrity. The difference is farmers actually work for a living and those trying to record farmers are doing so to defame their business, label them as a monster, and discredit their attention to detail or care for their animals.

I want to reiterate my point that for small farmers these cows that they "abuse" are their livelihood. The same as a business owner who owns a boutique or winery. Their business thrives when they take the best care of their animals, the same as a boutique owner and their jeans/dresses or a winery and their grapes. Happy cows produce more milk.