That Monaco is crowded with celebrities is no piece of news. Since 1869, when personal income tax policy became favorable, Monaco attracted very many individuals with high net income, such as movie stars, sporting stars etc. who became residents of Principality in order to benefit from personal income tax exemption.
Take, for instance, Roger Moore, Shirley Bassey, Ringo Starr, Karen Mulder, Eva Herzigova, race drivers Jacques Villeneuve, David Coulthard, Jenson Button.
But number of celebrities is far outnumbered by number of business people who enjoy country's tax facilities: retail tycoon Philip Green and Barclay brothers are Monegasque residents.
Being a resident of Monaco implies proving you have a place to live and are rich enough to afford a very high standard way of life. And I mean really rich, as a place to live in apartment blocks jammed into two square kilometres, either rented or bought, is extremely high.
Keeping residency implies proving you live in Monaco at least 6 months and a day per year. If you are rich, advantage of being a Monaco resident is that, besides enjoying a sunny, pleasant climate, you can live at same time in another country. The Principality is very close to main airports and is also easily reachable by sea, by car or by train. Thus, being a Monaco resident and working in another country is not only possible but it's easy especially speaking of UK citizens: laws in UK permit a maximum stay of 90 days (without counting day of departure and that of arrival!) for non-residents. Many UK business people reside in Monaco and work in UK without surpassing 90 days limit so that they are subject to Monaco lawas for taxation.
Having attracted so many rich resulted in a conflict of interests: many countries disapprove of this taxation policy, looking at it as an evasion from taxes in their national area. And not entirely wrongly! In fact, Monaco has been "tax-cheating" a little by attracting capital from high tax countries.
Looking at issue from perspective of Principality, seems to me only right to try and succeed to evolve with few means and resources a state so small has. Monaco developed from one of poorest countries in world (in 1860s) into a state with one of world's highest per capita income (around EUR22,000). And it was possible due to a strategic leadership of a resourceless country. It is after territory was drastically reduced that this personal income tax policy came into being. Attracting foreign capital become one of main targets for development. That's how Casino became grand and famous and emphasis was put on tourism, being raised at luxury levels.
After individual taxation regulations, in 1963 Principality came with another financial artifice: no tax for local company profits or dividends. Thus target was to enhance local business flourishing. This stipulation combined with an almost hermetic data privacy did nothing else than to increase even more foreign investments in Monaco.