Now, I keep noticing that SUVs, station wagons and hatchbacks almost always have REAR wipers...and Minivans. Why is this not a standard item, or even an option on most other sedans and coupes? I mean mid 90-s Integra coupes and Preludes (I think?) have wipers on the back. How are those back windows different from my 330Ci window or my wife's Mazda6's ? And sedans NEVER have a wiper arm in the back...why not? does this have to do with the angle of the rear window? If that's the case, it still doesn't make sense, when you think of the examples above... Any thoughts?