What you're seeing also includes a lot of selection bias.
Just as you claim that a few bad apples shouldn't tarnish all migrants, you also have to accept that the "good apple" migrants that you're speaking of can't speak complete good of all potential migrants.
I.e. you're making the exact same type of generalization, just the opposite way.
Have you? What have YOU done besides be born in the right country? Put yourself on the other side of it. What if you'd be born in Syria and had a lovely life until all hell broke loose a few years ago? Would you be fighting ISIS? Fighting Assad? Or would you be begging EU states to let you in?
[dead] comments that are good can be rescued if enough users vouch for them. To do that, click the 'vouch' link at the top of the comment's page (which you get to by clicking its timestamp). But please only do this for comments that are both civil and substantive.
As we've seen in all countries migrants especially those with families end up being massive positives for the country and its biggest defenders.