This is a difference in culture between Europe and the US: Most US employers won't notice that, because if they employ people across the US and not in an office, they'd hire than as contractors rather than as employees. In Europe, this form of contracting is much less prevalent.

I'm not sure what the cause and what is the result here, but it explains why Americans don't usually see this problem.

Yeah I know. We've tried to talk to some and have them on as contractors, but some did not want that (since that would have caused issues for them). Plus being from Europe, we really like to give our employees health care, vacation and all the nice benefits of an employee ;-)

For a lot of businesses isn't it a realistic option to just ignore the state governments? If the IRS says "jump" you say "how high?" But if the state of Pennsylvania starts complaining and you don't have a presence in that state, what the heck can they really do about it?