Quite common.

Many (not all by any means) wealthy people got that way because they're sociopaths so paying old debts because it's the right thing to do is not going to be high on their list.

It's also financially prudent in many cases to borrow money even if you could pay cash...that way the risk is on someone else.

And if you're rich enough and in a high enough position in society your credit score is mostly irrelevant so there's no need to sweat it. Pilots need clean driving, medical, criminal, and health histories...none of that applies to CEO's.