How do you ship 5000 people a day to say Mali or some other war torn place? You cant just dump them off the coast of Lybia, we aint Trump (yet).
Plus most dont have papers and can easily claim coming from war place (which many do, but I suspect most are economical migrants). This isnt easy to solve, look what Australia is doing (detaining immigrants in Papua IIRC in bad conditions to scare others).