Refugees have a really crappy visa regime, if they are caught outside the country that received them they risk being deported. While some try anyway it's not something that is likely to happen in a large scale. If Croatia offers a way to convert the asylum in work or study permit in the long term then for them it will be a better deal than what Germany offers.

I don't know how familiar you are with situation in Croatia, people are moving to Ireland and Germany because they can't pay their bills - they have small salaries or have no job at all. As /u/almakarlin said, it's a nice gesture but Croatia is not a 1st on the list of countries man would want to live in.

I moved from Portugal to Germany for the exact same reason, but if I was Syrian I would still choose the renewable and convertible refugee visa that Portugal offers than the 4 years and you go back to the shit hole that Germany does. Not that the refugees will be given any choice.