Regardless if the Queen Mother left her great grandchildren [specifically the York Princesses] any money, I would think that she did leave her grandson [in this case Andrew] some money, and he [and/or The Queen] is financing their lifestyle. I also wouldn't be surprised if the any monies left by the Queen Mother to Beatrice and Eugenie were in a trust, and they are using any interest and cant touch the principal. I think Mike was making a general comment [regarding the expense of Zara's profession] as they do support themselves, but they are not struggling like the average joe to pay the bills. I would think that the Queen will take care of her grandchildren when the time comes. But again, I am thinking trusts where they live off the principal with a nice little prenup for just in case. Her grandchildren will be well off but their children [Mia, Savannah, Isla, etc.] will have to work.
In addition, the rich don't travel like the rest of us. They tend to travel with other rich friends [on their yacht, at their luxury home, etc] so they probably don't spend that much. They spend a week or two at Friend A's house, and than they move on to the next place of Friend B's. Much like the old days of Edward VII, who would frequent the homes of other rich people.
IMO this is just another case of Beatrice can't win. When she had a regular job people complained that she took the job/internship of someone who really needs it...when she doesn't work people tell her to get a job. If she decided to stay in the movie business, whose to say that she isn't between gigs. Either way, someone is going to complain.
