Yes, i suppose part of the reason for these super long intervals is to reduce the amount of waste oil that is generated, but longer intervals are also possible because in the EU both Gasoline and Diesel are now ultra low suplhur, so the TBN of the oil doesn't deplete so quickly.
If i had a modern car that specs 30.000km intervals, i wouldn't go that long for sure, but 15-20k i would.
Engine oil prices are also quite a bit higher here, Mobil 1 of any flavor costs over 10€ / litre, although that is mostly due to taxes, at least here in Spain on top of the Value added Tax or Sales tax which is 21% , there is also another tax that is i believe 6 or 7 cents per liter on engine oils.