Where is criticism? I assume in domicile known as "the internet", you spell ridiculous as "rediculous"....just an assumption though. Most farmers in USA don't ride motorbikes for travel. Seems like pickups & cars dominate here.  You're in a different world, try to understand ours vs thinking we should change ours to match yours. Once again, we decided about 250 years ago not to put up with that mindset any longer. It's worked pretty well so far.

Here's your criticism of posted practices:

It looks like some of you are changing the oil on your cars at less than 100 engine hours, which is rediculous. Do you change your tyres when they get down to 5mm tread or run them down to the wear bars?

Many of us in the USA depend on common sense & life experiences rather than purely using numbers to decide when to change oil, tires, wearable parts, machinery, or vehicles in the whole. So yes, we may change tires before the wear bar touches the road.