Governments aren't exactly famous for being completely up-to-date on everything. The driving handbook you're complaining about was probably written 30 years ago... Back then, automatics really did suck badly.
With modern cars, automatics do get better fuel economy than manuals according to all the official fuel-economy tests I've seen. One big difference between the two that I've noticed is that in automatics, they tend to have taller gearing overall, and cruise at lower rpms (because of a taller final gear). This is most likely because it's so fast and easy for an automatic to downshift when it needs to, unlike a stick; this is especially important when using cruise control on the highway. The main problem with automatics (but not DSGs like VWs have) is the inefficiency of the torque converter. But modern automatics have worked around that really well with TCs that lock up and unlock very readily, so they're really not much different than a manual with its slipping clutch.
Luckily, here in the US, for all the things we do wrong with cars and drivers' licenses, there's no automatic restrictions I've ever heard about. I've heard of some states having such a thing on their licenses, but in reality I've never heard of them actually sticking that on someone's license if they took the driving test in an automatic. Almost anyone is allowed to jump in and drive a stick any time they want.