I'm sure it's just a question about vegan/vegetarian food not having same status as halal/kosher food. I doubt Muslims in Swedish jails would be forced to eat non-halal food. It's probably just a matter of economics. Preparing special food for one guy and have it delivered to him would cost too much money and take up to many man-hours. It's just not cost effective and prisons have a budget just like every other government run facility.