'Wealth redistributionists' aren't motivated by envy, as you imply. Rather they are motivated by the practical aspects of maintaining a healthy society. It's in the best interest of all if wealth ends up in the hands of those best able to employ it to everyone's benefit, ie the most productive members of society. The prevailing assumption is that the unrestricted free market is the best way to do this. It's now clear that this assumption is wrong, and that wealth tends to attract wealth entirely apart from the economic fitness of the person wielding it.

There is no such thing as an 'absolute' level of wealth, once basic survival needs are met. Study after study shows that people's perspective on wealth is entirely relative, which is why there were several recent articles here on HN regarding rich people who don't feel rich.

What exactly is a healthy and efficient distribution of wealth is open to debate, but a split where 1% of the population hold 35% of the wealth certainly doesn't seem either healthy or efficient.