[nisa]

The data might depend on how well it is gathered but it could be true: The mentioned safety-net is rather bureaucratic and if you don't comply with orders (like getting a job, showing up for dates) they can scrap it completly for up to 3 months - including rent! That causes homelessness and then there are lot of immigrants (not asylum-seekers) from other EU and non-EU countries that have no right to these payments.

The rising prices for rent in cities are maybe also an factor. Besides that most homeless have some psychatric issues like addiction or psychic-problems (not everyone of cource but it's a factor) and while there is treatment available it's often not accepted and not always successfull.