For example, UK Road Tax is now heavier on "polluting" cars, which mostly means "old". After two years, all cars have to be officially checked every year, forcing old vehicles off the road when the cost of mostly-optional maintenance becomes higher than the actual car value. Several cities block access to certain areas depending again on the "environmental impact" (i.e. age) of the vehicle; the European Emission Standards have been changed on average every three years, so anything linked to that standard changed accordingly. Most countries run, or have run in the past 10 years, "scrapping" schemes where people trading in their old car would get a direct government subsidy when buying a new one. This is all fairly useless, considering how study after study demonstrated that the largest threats to air quality in cities are old heating systems and industrial activity, and 90% of accidents are not due to mechanical breakdowns; but it does push people to get newer cars.

I'm not saying this is a negative thing (in theory it's quite nice), but in practice it's just another way to help car-makers.

Most countries also dish out subsidies directly to struggling car-makers; companies like Renault and FIAT are seen as "national champions" and treated accordingly -- although this is now illegal under EU competition law, nobody complains because every manufacturer based in Europe will have enjoyed some "public love" at some point. After all, car manufacturing still employs, directly or indirectly, a lot of people.