Why still manual lenses?

Not only that, when shooting birds in trees, AF will lock onto leaves or branches or everything BUT the bird. MF is crucial in situations like that. Using my 100-300mm is extremely frustrating, because focus-by-wire is far slower and inaccurate compared to using a direct-drive manual lens, mainly because I need to half-press the shutter AND focus at the same time. Few birds have will pose long enough to allow me the luxury of struggling with AF/MF.