Sent back, no. Problem is, there are coming more of them each day, and the border needs to be closed for those types of immigrants (at least for the moment). We can't even handle the integration of the current immigrants, let alone let them transform the big cities slowly into islamic ghetto's.
Should they be sent back because some lack the moral initiative to actually do something?
Communism essentialy stimulates the so-called 'free rider problem'. Large governments stimulate the 'moral hazard' problems. With a small government though, greed is good - it encourages innovation and stimulates hard working. Hell, capitalism is the best system out there because basically all it does is exploit greed. Yes, greed is good.
And that is the entire point! I have to write response papers on political theories, and I often come back on the greed part. Greed is one of the main causes of war. Greed makes social structures fall apart. Greed is the goddammed worst sin there is in human life.
And to come back on the point I formerly quoted, PVV judges all immigrants on those few who come here out of greed.
Actually, most are coming here out of greed... Our greed too. I recommend you look up 'de resolutie van straatsburg (1975)'. Explains a lot of things, and gives more reasons to be angry at the mess the PvdA left us.