Well for most the reason you will hear is because of awd. How ever I been in the car hobby a long time cars and coffee every weekend modded all my own cars tuned all my own cars been basically in the car culture 24/7 my whole life and I can tell you in America anyway there is a lot of I have to have the best to be better then the next guy. It goes so far in our car culture that people wil go hunt down build sheets of entire runs just to find if they have a one of a kind build and color combo and then they advertise it. We are also a culture of well we have to HAVE ALL THE OPTIONS nothing else will do its fully loaded all the way or nothing.
Why did some buy the M50? well because it was the top option... biggers better right? Most people buy top models for performance or ego or any combo of reasons but the i4 and i4 M50 are a strange one. Even though its one of the few cars that almost every reviewer has said the lower trim actually is the better driving and handling car, to which I can say yes because I have also owned both for some time and the lower trim is actually the better driver, people still go after the mental satisfaction of I have to have the higher car because its better.
Just like the with the parking and driving add ons that every one is just having to have as if in the history of driving every car has been junk and just ran off cliffs with out them. But they are an option and well we have to have fully loaded even though the car drives and handles just fine without them and we honestly dont need anything else to take our eyes off the road .
I too am guilty I wanted and now have the M50 I dint get a full loaded one though. I also had the edrive 40 and honestly the edrive 40 is just fine and its the better handling car but yeah its not the top its not the fastest its not the M badge its not got the clout and stroking our own mental ego in this country is a bigger deal then most will admit.
I mean I got it for the AWD ( even though it only snows like 5 days the whole year) and the more power (becasue 95% of driving is stop light to stop light) and because once fully loaded it was only 10k more then the e40.... LOL (only 10k pft peanuts)... people will justify it anyway they can before admitting it was because we are males and some times females and we need the biggest best and fastest regardless of any real practical reason just to make ourselves happy.
Honestly I bought it for one reason it was the top model and I wanted to say yup thats the M50 baby

and to be totally truth full no one needs a car that cost more then 30K NO ONE after that its just to please ourselves and no longer for anything practical.
Merry Christmas. Feel free to send hate mail to.... Kidding, Now go out and enjoy those EVS