People who are born to money never need to display it. They have the quiet confidence that it's there when they want to use it, and never need to 'prove something'.
So their clothes are very often not flash, and maybe even a good brand that was picked up cheap at a Goodwill Store.
They might drive a good but quite old car that isn't/wasn't 'top of range' like maybe a 5-year-old Mercedes C-class. Why have an extra-expensive sports car? The C-Class is good enough for local driving up to say 300 miles. Anything further and you travel by air and very probably in Business Class.
We were already friends before she knew what I did and certainly very good friends before she had any idea of my salary.
That said I'm not 'noveau-rich' just well-paid for my age and area.