'They want not to be pedophiles.'

Unfortunately not true. PIE people genuinely believed they were doing good!

'The group's stated aim was "to alleviate [the] suffering of many adults and children" by campaigning to abolish the age of consent thus legalising sex between adults and children' (Wikipedia)

This is because humans are basically horrible self serving creatures, bending their beliefs to what suits them.

Even Hitler thought he was doing the world a favor! (just thought I would bring in Hitler to make the discussion complete)