They do not make up the majority, and most of them have other assets:

"only about 12% of U.S. households have a net worth over $1 million."

https://finance.yahoo.com/news/guess-percent-people-1-millio...

I’m in that 12% (fortunately). But I’m far from the 0.5%. The 0.5% have complex diversified assets. “Normal” millionaires like me are mostly real estate and market. We are vulnerable both to market losses and, if the economy crashes, much lower property values.