I would not specifically say people are against it, it is just one of the less enjoyed kinks.

While I do not participate in it, or have any desire to, I do not hold it against anyone that does it, or am against it as an activity.

You will find that not all kinks were created equal. You have things that the vast majority will indulge in (e.g. spanking), activities that may have of people enjoy (let's say anal), and some activities that only very few people enjoy (scat being one of them).

Generally, as things get more extreme, less people want to do it, but I wouldn't say they are "against" it in the sense that they would hold a grudge against people that do it.

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