Selection bias. You're specifically selecting for people whose only money is money they inherited; failures, in other words.

There's a lot of children of rich people who are quite successful in their own right. Bill Gates, for example, did not come from a poor home. And the other thing you have to watch out for is reversion to the mean. It's unlikely Gates' children will outdo him.

So you don't know a lot of people who inherit then. That is probably because most of those people do not show off this money and you will never know.

You only see those that show of and why not to say it? what you want to see based on your prejudices.

I have known a lot of people who inherited, some of them are useless or dysfunctional, some of them are really resourceful and know how to make good use of his money. E.g the creator of "Zara" inherit a small clothing store: http://www.zara.com/

Now is one of the biggest in the world.

Half of the greatest philosophers, mathematicians, physicist of all time came from wealthy families, so they could dedicate time for non-primary necessities, a luxury even today.