Yeah I've often wondered this myself. Seems now that everyone wants a diesel whether it be a 4wd, 2 wd, wagon, sedan, ute, hatchback, SUV you name it.
Diesel is in fashion.
My prediction is the novelty will wear off and people will go back to petrol.
Petrols are cheaper to buy, run and service.
They burn cleaner and they way high tech diesels are going they're simpler.
New petrol tech is now producing more powerful and economical petty engines so fuel
Economy will no longer be an issue.