It doesn't seem that they are. And as for the claim in the article that "no-one is begging", anyone who has spent more than 15 minutes in Helsinki knows that's not true. Most of the people begging might have come from abroad, but they're there. And when it comes to the statistics, I found this reference:

"In addition to the homelessness visible in statistics, the existence of undocumented migrants is a phenomenon connected to homelessness. An undocumented migrant is a person, who does not have a legal right of residence and whose residence in Finland is not known to or permitted by the authorities. Different estimates by experts on the number of undocumented migrants in Finland vary between 500 and 3,000 people [...]" (PDF report downloaded from https://tinyurl.com/ycybdjtc)

Edit: Additionally, EU citizens may legally stay in Finland for months, are many are known to do so, even if they can unfortunately only make a living panhandling