I think this sentiment can be utterly counterproductive.
By virtue of being rich, the rich can sow the seeds for their societies future wealth in many ways. One of the big ways they do this is by spending on things that seem frivolous to most, but slowly become things that everyone takes for granted. This is what progress is.
I could give endless example, but here are a few:
- Passenger air travel used to be the preserve of the wealthy - now this is something that is so cheap that air travel is now completely de-glamourised. i
- ABS brakes were once only in expensive and powerful cars that only the rich could afford. Now they are not only standard fare, they are mandatory in many jurisdictions.
- The first plasma TVs cost in the region of $10,000 and were definitely out of reach for the average person. Now you can get much better TVs for a 50th of that.
While that top end Mercedes is the definition of a true luxury, you should consider that the reason that the car you likely drive today contains features that were first bought by the rich, and their frivolity actually led to useful innovation that are now available in pretty much any car you can think of today.
A more appropriate example for Slashdot is the amount of money many here would be prepared to spend on high end computer gear, particularly back in the day when high end PC gear was incredibly expensive. This wealth effectively "trickled down" to most people who can now afford computers that once were the preserve of the frivolously rich (or of geeks).
So don't knock the spending habits of the wealthy. We need them to continue to spend on the things that we cannot yet afford because one day, all of us will be able to afford them once whoever makes them is all tooled up and wants to recoup their investment (and make a bit of money for themselves while they are at it).