Noblesse oblige

Do you know noblesse oblige? I just knew this word recently. This mean is below.

the moral obligation of those of high birth, powerful social position, etc., to act with honor, kindliness, generosity, etc.

Souce: Dictionary.com

In US, it appear that rich people make a contribution.
For example, Bill Gate founded "Bill & Melinda Gates Foundation(B&MGF)". And Warren Buffett made a contribution to B&MGF.