Jewelry
Nothing more, nothing less. Its like watches. In watches anything over about $40 or so is just status symbol jewelry. Sure you can buy a nice $multi thousand Rolex, but does it keep better time than the nice $30 or so (prices have gone up a bit since I last got a watch) simple Seiko (add about $10 for the nice Twist-o-flax watchband I like).
Sure you can avoid silly (thankfully we don't have them here [yet] in sunny California) congestion charges, but other than that, what's the point. Given the fact that silly plug in funny stuff doesn't work for long drives (it is about 300+ miles from the bay area to the LA area), and vacations are even a bit more (I plan a trip over 1000 miles this summer), they really don't make sense.
Of course what do I know. my Mom (bless her 94 years!) has an older Prius that she likes simply because she doesn't like going to the gas (petrol) station that much. My dad was always amazed at the fancy display that showed what energy was going where that was in the middle of the dashboard. My take (having driven it a couple of times) is that the silly one button start-stop thingy is a terrible user interface (kinda like Windows shutdown being under the 'Start' button.
Such is life.