Charles WILL follow his mother, and then Wills will become the Prince of Wales and first in line to the throne.
If tourism lags or something due to no royalty and they feel they need a mascot they could probably hire Michael. Of course that could lead to other problems what with two places serving only bad food and having a similar mascot so they might get sued by Burger King.
I imagine even dragging the suit through court would still be much cheaper than supporting the present cast of clowns...(why haven't they been sued by McDonalds?)
On the bright side, as an employee of the people and one that believes in a republican form of government at that, they at least wont have to hire his children.