You have hit the nail right on the head. I am absolutely fed up with the mother and three kids that are using the carpool lane or dad and one kid, since when did kids have their own cars?
Since when are kids not people?
The idea is not only to have people leave cars at home, but for more efficient use of road space. In the same logic as above, we can state that disabled people that are being driven to doctor's appointments should not be allowed to use carpool lanes. See what kind of reaction you get there.
Here's another example -- because the mom has to leave earlier to go to work because she can't drive in the HOV lanes, she now has hire a nanny, who will have to drop the kids off. Now we have not one, but TWO additional trips on the road, one taking kids to school, one -- picking them up.
One of the options being proposed is HOT lanes -- High-Occupancy Toll lanes, where single drivers can use HOV lanes for a price, which directly depends on the occupancy of the lane, so that traffic keeps moving at all times.
BTW, I'll try to look this up, but I think that in LA, what was said above about carpoolers is quite true, given the high rate of SOVs on the road.
Be careful what you wish for. The L.A. carpool lanes are being opened up to people who are willing to pay a toll to drive in them.
Personally, I think this is a good idea. You pay more if you want to drive faster.
The Netherlands is implementing country-wide road-based pricing within the next few years, where they are abolishing ALL road taxes and will make you pay only for the km that you drive, based on the car you drive and the traffic conditions on the road, in some cases possibly providing incentives for driving on certain roads (road trip Mileage Run, anyone?

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