They get off on spreading their negativity
Kids learnt a trendy word (in this case; grooming) and starts throwing it around at everything they read and comprehend on surface level. Since it's what the general public deem as "morally wrong" they start policing everything so they feel better about themselves ¯_(ツ)_/¯
In actuality, the call is coming from inside the house. It's the fact that they *actually* enjoy reading this, that they feel the need to call it out to show their level of "maturity", that they're morally above than the people who explicitly and openly enjoy reading this trope without complaining. They just don't want to admit that this is their source of guilty pleasure
real
It amazes me how many people waste hours of their life they’ll never get back reading something they hate so much, I don’t understand it like there has to be other things you can do with your life that you’ll enjoy