Personally I can't imagine anything more peaceful and easy than staring my vacation with MME, continuing it by letting others do the driving, and finishing it with that MME bus whisking me back to reality. The whole parking, remembering WHERE I parked, navigating the roads (admittedly, they do have fantastic signage), and walking to and from the car just feels like a hassle to me and we won't be doing it again. For me the transport system is just part of the magic. And our last trip (and only one with a car) was at AKL so it's not like we were on the monorail or had easy trips to any of the parks.
I wouldn't be surprised if we felt differently if we were slogging around a couple kids and all the accessories but we're not, it's just us two, and the wait for a bus has never been too long nor have we had any bad experiences. We like people-watching and can amuse ourselves happily at the bus stop so no worries there.
Driving just wasn't fun, for us it was too ordinary, too much a connection with our non-disney lives. Others obviously disagree so, hey, enjoy your cars and I'll enjoy the slightly less crowded busses and boats!