Then why do they keep coming to kafir nations? And if they won't integrate and participate in our society, why should we have them in our countries? It seems pointless from both points of view.
I don't know why they go there. I don't know why Jews and Hindus go there too. Btw you don't have to paticipate in society as long as you pay your own way and stay out of trouble. What is your definition of integration? It is also not illegal to be a recluse is it?