The irony is that part of the "why?" is because of the pervasiveness of tepid coward attitudes like that is directly enabling. Maybe the problem isn't even refugees or a small subsection of them, just don't shield people from consequence out of fear of being "xenophobic". Systems of justice need leashes kept on them, public dispositions of apathy creep into law enforcement as well. This is how literal rape/grooming gangs in some parts of Europe go relatively unchecked.