Mexico has a similar law. Near where my parents live, they recently started enforcing it with some vigor. The problem being that foreign musicians (mostly Americans) were playing shows for "donations". Whether that was actual donations or bar owners donating was unclear, but either way it was plausible that these people were displacing musicians entitled to work.
The shorter version: jackasses getting around a law cause more laws, ruining things for everybody.
I have another interpretation: bad laws are impossible to enforce in a just way. I have no idea why anyone should be required to have a special visa to work in the US. Because we are selfish?
"I have no idea why anyone should be required to have a special visa to work in the US. Because we are selfish?"
Seriously? If the US didn't have immigration requirements, half the world would move there, causing the society and infrastructure to collapse? I can't see how unrestricted immigration benefits the US at all (I'm not a US citizen).
I'd wager that A: the disparity between countries is larger and more well-known now, and B: the ease of physically travelling to the US is far easier now.
The Model T started production in 1908 and the first commerical airline flight was in 1914. The state of the art for sea transportation around then was the Titantic, which sank in 1912. So maybe that had something to do with it.
The shorter version: jackasses getting around a law cause more laws, ruining things for everybody.