Physical castration would be pretty inhumane for those that haven't committed any crimes, especially for the ones that are capable of attraction to an adult. It's another story for ones that have acted on those urges.
As for communities, there are some that have the support of doctors and human sexuality experts. This is what the psychologist, Jamse Cantor had to say about the mutual support group/forum, Virtuous Pedophiles:
"It is hard to imagine someone who would feel more isolated than someone who recognizes he is sexually interested in children. In my experience, it is in those phases of greatest desperation that a pedophile is most likely to do something desperate, risking harm to a child. Mutual support among people who share the same daily battle with their own desires can go a long way in addressing the extreme isolation, serving as a potential pressure valve, adding layer of protection, helping pedophiles to keep their behaviors under control."
Is it really inhumane though?
They possess predispositions that are at odds (should they be acted upon) with the laws of most societies, and are of such a nature that repressing them will cause them continuous mental anguish even with therapeutic & peer support.
It strikes me as more humane to remove that one aspect of their life they can never fulfill in order to live a more fulfilling life overall - for without their sexuality, they're not missing out on the qualitative experiences that the rest of us experience.
Yes, their overall sum of potential human expression is reduced, but in such a way that they improve in other areas - in terms of freedom, in terms of social acceptance, and so much more.
Is that not a world you'd rather live in?
Where pedophiles upon expressing their sexuality are guided to the nearest medical center, with empathy rather than repulsion, so that they can continue their lives - one small part of it removed - without worrying those around them.