I doubt there is any law anywhere prohibiting a millionaire or billionaire from moving themselves and their families to a new place and living a middle class lifestyle under a new name.

Advertising one's wealth is a signal for "I seek validation" and "Please appreciate me"/"Be my friend because I am wealthy"

I doubt anyone is actually stopping Bob from quitting his job, moving to a new country, and living a quaint lifestyle.

Personally, I've up and moved and gone to live in a tent, just to see what it was like and essentially test myself and test the lifestyle of a vagabond.

It really showed me that, as a man, for the most part: you have no worth outside of what you provide for others. Men are expected to provide something for their community-- that is the basis of their social status: competencies (i.e. capable of productive things) and contributions.