Indeed, having two cars when the main salary is just a teacher (they are paid pretty low wages) is calling for trouble, so there is some caricature in the example.

Now I agree that the problems must be more acute for those below middle class. Having said that, if you must be low income class, France is not the worst place in the world to be so (although UMP is trying to make strides in that direction).

Anyway, cars are a very real trap for a lot of people. It is a pit of spending (all the more so because it is a universal symbol of status, and people tend to buy a much more expensive one thant they need). Cutting on that expense allows a huge improvement in financial flexibility. Still, many unrich people are obsessed about them and will sooner stop using hot water than their car.

Earth provides enough to satisfy every man's need, but not every man's greed. Gandhi

Actually, teachers and postmen are very quickly moving down the economic ladder ;  teachers are paid wages that don't really make one able to maintain a middle class lifestyle. And nothing proves their two cars were in themselves expensive ; they could have bought second hand old small cars at a couple thousand euros...

Un roi sans divertissement est un homme plein de misères