Earlier quoted context omitted.
A US SaaS hasn't got tax, legal, culture issues when selling their products in Europe. So how can all of these be issues within the EU?
Have you ever tried to sell something in English to a French company? Have you ever tried to sell something in Russia without "having a connection" to someone? Why does Dropbox have a Irish HQ?[0] [0]- https://www.dropbox.com/dublin
There are two main reasons why companies set up European HQs in Dublin/Ireland:
1. Avoiding tax. Ireland has a low rate of corporation tax and some fairly large loopholes. See the Double Irish arrangement and the Dutch Sandwich[0] set-ups.
2. Avoiding privacy protection. The data protection authority in Ireland is tiny[1] and severely under-resourced, so finds it hard to enforce European data protection standards which are significantly higher than in the US (which has pretty much zero regulation when it comes to privacy)
[0] https://en.wikipedia.org/wiki/Double_Irish_arrangement
[1] http://i.imgur.com/IKHC2Ud.png - This is the office of the Data Protection Commissioner in Ireland. A tiny office next to a supermarket. This is the authority responsible for policing privacy for dozens of huge multinations in Europe, including Facebook.