Matt,
Interesting point you have raised, in an odd fashion. I think that the 'basic life skill' is actually using buses, taxis and trains and not driving. If you are in a position to use public transport, you need to be able to USE them. I use public transport about twice a year - when i attend a drinking event with some friends. The remainder of the year i drive. I lack the skills to work out timetables and bus numbers ets. and resort to phoning the bus/train to get advice.
Re buying new cars every 3 years - see the Audi above. 1999 A6 1.9tdi, 203,000 miles and running like a dream. Sold to my mechanic for £450 and he knows it is mechanically sound. I have owned it for 7 years and 9 months and put and average of 9000 miles per year. It still provides 50mpg. My new car is the newer version - but 2.0tdi, mpg is guessed at 44mpg. It is 7 years old and is costing me £7500 - this is a good price for here and compares with English prices. I would hope to keep it for a number of years - hopefully at least 9. With proper servicing from an Audi specialist (not dealer) it should last to 200,000 miles.
Get your calculator out and do some sums, the 3 year change always seemed madness to me. The advantage is warranty and relatively hassle free driving but you have to pay for this.
Richard