Some categories of people are more likely than others to be affected. Migrants, for example, may lack support networks of friends and family, familiarity with English and knowledge of how the benefits system works, and are vulnerable: people from the east European accession states – including Poland, the Czech Republic, the Baltic states, Hungary, Romania and Bulgaria – make up nearly 30% of London's rough sleepers. This is an extract from The Guardian newspaper you highlighted.
If we didn't have open borders because of the EU, the 30% of London's rough sleepers would not be here. Never mind they will soon get on the benefits gravy train if they stay here for long enough!