I respect their decision.

People eat meat despite knowing how pigs are kept. People commiserate with service workers but are still upset and when their order is late. People watch soccer in Quatari arenas and Formula 1 tracks built by de-facto slaves. People drive their cars, knowing and ignoring that the petrol comes from one dictatorship or another that has probably shot a few civilians this week. We buy 100 different products each moth, most of which are made by companies whose C-level and owners also use their enormous wealth to support one destructive cause or another. Etc.

It is impossible to exist in our world without passive participation in many, many large and small kinds of structural injustice and plain evil - but somehow we get through the day anyway.

I don't see that JKR and HP is much different than any of the above examples; so I try not to be a hypocrite and let them enjoy HP.

Don't get me wrong: Its admirable whenever anyone makes secifaces to facilitate a greater good. But there is no point letting these things damage our interpersonal relationships.