Part of the reason may be
- they're a small family, with - due to a lot of wealth - a very powerful prince
- money
- have the ability to keep things quiet, seeing they probably control the press
- because they're a small family, there is less scandal.
Its not to say there isn't scandal, its just a matter that money talks
here's a few links for this family
link 1
link 2
link 3
maybe here
link 4
link 5