I tend to think that those having $1 million and up to possibly $30 million likely worked hard and/or had a big dollop of good fortune. At this level of wealth I have no issue with it being left for heirs.

When we reach hundreds of millions and up, one wonders if it's solely due to hard work and good fortune. Also, by this point, it's nearly certain that taxes have been (legally, most likely) side-stepped.