By the the way you are talking you imply that your car is at least 14 years old, now depending on the car, but going back 8 years or so most cars had a service interval of 6,000 miles. You should be using a standard mineral oil.
In newer cars, full/semi oil is used, bhp has been increased, noise levels decreases, emmission levels decreased, and engine sizes sold not really changed. Something has to give, in more modern engines they will use oil.
It's not great that this happens but a small price to pay for your increased
levels of comfort.
At the end of the day it's your car, it's your responsibility, you have to take care of it. In general it is most peoples second largest expense (after a house) but it's usually neglected. There should be as ISPCC for cars. Some people shouldn't have them, they can't and won't mind it.
Cars have moved on a lot in the last 10 years, people maintain their lap tops, lawnmowers, central heating, washing machine, dishwasher etc better that they do there cars. Yet when something does go wrong with a car they will always try pass the buck.
We had a customer here yesterday, slight imbalance in front shocks, required l/h front required to be replaced, 60,000 miles, living in the country, swears blind that he has never hit a pot hole etc in the whole life of the car so far. The problem must be with the manufacture's shocks. My friend down the road had the same. How do you talk to a person like that?
"cars only getting run in at that mileage" "I have a tractor at home with twice that mileage and never a problem", Some people you just want to shake sense into them.