I was told Doyle does play every now and then on the site, mostly for promotional purposes and generally in the highest limits. I also believe he doesn't have a financial interest, but gets paid consultant type fees. Most Americans, especially those as high profile as he is, would be stupid to ever own a piece of an offshore place and even dumber to admit it.
I remember when you could play 3-6 with Phil Hellmuth at Ultimate. Never could get into the tables, the list for the game was like 45 names long and there were something like 100 people watching the table. The stars love playing and telling you it is them. Any star will tell you its good to be recognized, people are always doing stupid things just hoping they can say they beat you out of a pot or made a move on you.