It's not a theory. It's socialism and it works fine in Scandinavia, Switzerland, and a bunch of other places.

Im Danish, and I approve of the welfare state system, but we still have people cutting down EV charger cables etc here.

Scandinavian scrap metal thieves organize trucks and cranes to steal copper roofs from old churches and rip down railroad overhead lines all the time.

Free healthcare and education, guaranteed housing and social safety nets make little difference.

Some people will stop at nothing to get more, no matter how much they already have. (Applies to billionaires and paupers alike). I guess you could call it having an entrepreneurial spirit.

No one steals car stereos anymore though, because you can't sell them to anyone. That mechanism could be put to more work. Heavy, EU-wide supervision and enforcement against scrap metal dealers would probably make a difference.