A young colleague of mine spent a semester of college in Denmark.
His student visa assigned him a unique ID number (similar to an SSN) that would be required of him to do ANYTHING in Denmark. To do any banking, rent an apartment, buy a bus pass, check out a library book, etc.
His visa came with a very stern warning that he must be out of the country by June 30, 20XX. And that the ID number he had been assigned would turn into a pumpkin on that date.
Some countries, it seems, take this seriously.
Illegals were virtually unheard of, other than a few "wetbacks" near the border.
Denmark doesn’t cater to the cabal of big business that wants cheap labor.
From Wikipedia: “Denmark’s Muslims make up approximately 3% of the population and form the country’s second largest religious community and largest minority religion.”
Sounds like Denmark has other “immigration” problems.