Well they're rewarding relationship activities between consenting humans of mature age. Any of those ignorant criticisms you mentioned is ignoring these facts. These scenes allow for vulnerability and intimacy based on role-responsibilities, just like traditional relationships do, but many find DD/lg or Pet Play roles less confining than social norms.

If you're asking to learn more in earnest, I appreciate your curiosity & suggest any of the books, blogs, or youtubes on these topics.

If you're asking because you see a point in the ignorant criticisms & want to give us a chance to defend ourselves, I would suggest the same as above & add that it's not our responsibility to justify our lifestyles to tourists. People in a scene often find it difficult and exhausting to explain their lifestyles to ppl outside of the scene - especially if those asking aren't interested in participating.