It's even worse than having gotten it from their parents. Many of them lied, cheated, or stole, to get their money.
For example, Bill Gates got his start in the computer operating system business by telling IBM that he could sell them something that he didn't really own, and then tricking the actual owner into selling it to him for much less than the price would have been if he had been honest about who the real customer was.
Lucille Ball worked out a contract that let her have the recordings of "I Love Lucy" for just the cost of recording, by pretending that it was just to be able to sell them to her kids. The TV company didn't realize until later that they had sold her the rights to the profits from the reruns without even realizing it.
Donald Trump financed casinos by borrowing money that he wasn't going to be able (or willing) to pay back, used some of the money to put his name on practically everything in the casinos, and then after the casinos went bankrupt, forced the creditors to pay him even more money to be allowed to leave his name on the stuff because it would have cost to much to replace everything.
George Washington inherited incredible amounts from deceased relatives. And most of the actual work was done by slaves.