As a sweeping generalisation: Europe has chosen to value more stable employment opportunities with lower potential upside over highly volatile employment opportunities with larger potential upside. America has chosen the opposite. You're speaking as if there's an absolute truth in which model is better, but as we're finding in this very thread, American people are coming to Europe to build businesses (and Europeans are going to America to do the reverse).
I won't rehash what brnt has said in their reply, but I will echo their sentiment: The System is me and my friends and my family and my co-workers working together to provide healthcare and education and security to each other. I pay taxes for that reason.
Every country within Europe is different in some capacity so it's difficult to say with absolute certainty that he is breaking the law -- the language in my comment was vague because I'm mostly addressing the spirit of his behaviour, rather than the law. That said, certainly in my European country he would be open to issues with the tax authority if he were to attract their attention.
The United States is very permissive when it comes to employment, the majority of states could be described as "anything goes" (relative to Europe) and so dodging employment taxes is pretty much fair game... whereas in Europe a lot of regulation exist very specifically to address companies organising their business in this way. I'd be very surprised if he didn't face significant fines (I don't know of any examples of this behaviour leading to prison terms, but significant fines are very common and serve as a deterrent).
You're cheating the system, though. The system exists in order to support the way of life in these countries, by bringing your American employment attitudes to Europe you're not really building a company in Europe by any measure: you're building an American company. Your company is benefitting from the robust systems in Europe, without contributing. There are people you want to hire in Europe _because of people paying their share of taxes_. If you don't want to pay employment taxes, if you don't want to offer maternity leave... stick to America.
Personally, I think there is a strong argument to make for the value of America-style lax employment rules when it comes to startups, absolutely, but please don't bring those to Europe by gaming the system. Hiring people as contractors to avoid obligations is an age old way to game the system, and eventually you'll be caught and face penalties (unless you're smarter about it, so I guess my advice is actually: be smarter about it (don't announce it on HN for example!)).
I won't rehash what brnt has said in their reply, but I will echo their sentiment: The System is me and my friends and my family and my co-workers working together to provide healthcare and education and security to each other. I pay taxes for that reason.