Most people imagine that if they lose their homes, the fate that awaits them is the one they step over each morning on their way to work.
Most people don't have contingency plans, should they find themselves out of a job, and evicted from their residence, with no family or friends to assist with temporary resources.
If I lose my home, and have no savings or sufficient income, the local government will provide accommodation. At short notice, for a single male, that's likely to be a pretty grim hostel, but it exists.
Example: https://www.richmond.gov.uk/if_you_are_homeless
Advice about this from a charity: http://england.shelter.org.uk/housing_advice/homelessness/gu...
So, following the charity's advice, it might not be true that the local government would provide help -- but that would still be most people's assumption.
Another problem is people coming from different areas, say from North to South, who are just offered a bus ticket back there.
That said, in the UK at least, if you have no income you'll get the same level of cash benefit as anyone else so there is absolutely no need to be begging for money. Those that do either have a dependency problem or are just scamming.
Most homeless people in Amsterdam however have psychological and/ or drug problems that make it impossible for them to live in a home or in a shelter.
Note: the first part wasn't a criticism of the site, just a little bit of reflection. I'm actually impressed they have such some sort of information/guidance available
The proof of homelessness might be an eviction notice? I have no more experience than you in this matter.