This article is about migrants/human traffickers leaving from Libya, and does not mention Syria. It is very incorrect to conflate the two situations.

Here is a vague overview with a map if you are unaware: http://www.msnbc.com/specials/migrant-crisis/libya

I believe the "burden" is felt differently by countries closer geographically, socially and culturally. How much do they get paid in benefits compared to the UK for example? What are the housing costs and conditions offered there?

Considerably lower but probably it matches to GDP-PPP margins.

Perhaps illegal immigrants who are just seeking economic benefits should be returned after checking their cases even if their skills are needed simply because they have entered illegally. But, Mediterranean sea is not the right place to filter them.