I don't think it's a must.. but it should definitely be encouraged. I think the move to Automatics was a dumb move in drivers ed cars. It just furthers the "dumb drivers" disease by starting them as just that..
Pedal pushing mindless zombies that have a good perchance to put their bumper into your rear.
I REALLY wish I had the chance to learn on a Manual. My parents HATE them and actually refused to allow me to learn saying that it's more distracting and dangerous than driving an automatic. The only way I learned was driving a 4 speed gator.. and even then I still suck 7 years later (I don't consistently drive a stick.. maybe 2 times a year at the most).
I've learned over the years to keep my cool when I KNOW that learning to drive stick is one of the best things you can do to learn the practices of safe and defensive driving (riding a motorcycle is the other).
It's not only sad.. it's pathetic. VERY pathetic. Speaking of which.. the local schools in Kalamazoo use Priuses exclusively.