In my experience, how the wealth was gathered is usually reflected in their overall behaviour.
Someone who started out "poor" or as middle class and worked his way up to becoming a billionaire simply by putting in the hard work, doing what needs to be done, and most likely also being lucky enough to have made the right decisions at the right time... in my experience such people will usually understand the value of a single dollar, be humble enough to remember where (s)he comes from and what it took exactly to get where (s)he is today. These are the people that will have much respect for the mailman, the garbage collector and the hamburger flipper.
As for those that are rich simply because the parents were rich and didn't care to properly educate their kid...
Not so much.
Off course I'm painting a stereotype here. I'm kind of forced due to the topic.
Obviously you'll find "exceptions" to these stereotypes everywhere.
Which type do you feel is the more common? I find it hard to guess because we're skewed by what we hear, and the more extravagant spenders do make the news, but personally I think the humble rich are more common.
The Everyday Lives Of Frugal Billionaires