i wish the font one would hide as well. it gets dirty and degrades the picture, or it gets water on it and looks all weird. same the with ones under the mirrors, they get water drops on them and it messes up the picture a ton.
As nice as that would be for city parallel parking I find that reverse parking is the best since your more in control of where your vehicle goes, you can line up your wheels better, etc. So having a similar flap at the front would be a bonus to me. But as long as its easy to average where the front end is from how i'll be positioned in the drivers seat... that will be good enough for me.
Front and sides I don't really care about at all, true. Just the rear. The front is all about averaging, I've driven many vehicles before without any darn cameras and I've been fine. The rear just aids a lot when you can't see crud out of the rear. The fronts are completely unnecessary in my opinion.